How severe is CVE-2021-21235?

CVE-2021-21235 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2021-21235?

CVE-2021-21235 affects the following packages: kamadak-exif (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2021-21235?

Update kamadak-exif to 0.5.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21235 is resolved across your whole dependency graph.

How do I detect CVE-2021-21235 in my crates.io dependencies?

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

How do I mitigate CVE-2021-21235 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2021-21235 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-21235 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-2021-21235?

CVE-2021-21235 has an EPSS (Exploit Prediction Scoring System) score of 1.5%, placing it in the 75th 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-2021-21235?

CVE-2021-21235 is classified as Uncontrolled Resource Consumption (CWE-400), CWE-835 (CWE-835). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-21235 published, and has it been updated?

CVE-2021-21235 was published on January 6, 2021 and was last updated on October 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀

🦀 crates.io

Not in CISA KEV

MEDIUM severity

CVE-2021-21235 — kamadak-exif

MEDIUMFix: kamadak/exif-rs@f21df24

CVE-2021-21235 is a medium-severity (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in kamadak-exif. A fix is available for kamadak-exif — see the affected versions and patch details below.

kamadak-exif vulnerable to Infinite loop when parsing PNG files

Also known asGHSA-px9g-8hgv-jvg2RUSTSEC-2021-0143

Published

Jan 6, 2021

Updated

Oct 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

1.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs75th percentile — riskier than 75% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🦀kamadak-exif

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

Description

Impact

Reader::read_from_container can cause an infinite loop when a crafted PNG file is given.

Patches

Version 0.5.3 includes the fix.

Workarounds

No workaround is available. Applications that do not pass files with the PNG signature to Reader::read_from_container are not affected.

References

For more information

If you have any questions or comments about this advisory:

Open an issue in github.com/kamadak/exif-rs

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`kamadak-exif`	≥ 0.5.2&&< 0.5.3	0.5.3`cargo update -p kamadak-exif --precise 0.5.3`

Affected Products

1 product · 1 configurations

Application

kamadak-exifkamadak-exif_project

1 version

0.5.2

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kamadak-exif, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update kamadak-exif to 0.5.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21235 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

### Impact Reader::read_from_container can cause an infinite loop when a crafted PNG file is given. ### Patches Version 0.5.3 includes the fix. ### Workarounds No workaround is available. Applications that do not pass files with the PNG signature to Reader::read_from_container are not affected. ### References * <https://github.com/kamadak/exif-rs/security/advisories/GHSA-px9g-8hgv-jvg2> * <https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21235> ### For more information If you have any questions or comments about this advisory: * Open an issue in [github.com/kamadak/exif-rs](https://