GHSA-xxmq-4vph-956w is a medium-severity (CVSS 5.3) vulnerability in comrak. A fix is available for comrak — see the affected versions and patch details below.
Comrak vulnerable to production of excessive output when parsing Markdown (GHSL-2023-048)
Real-World Exposure
comrakReal-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
comrak is vulnerable to the upstream cmark issue, "Issue revealed by fuzzer". A large number of references in a markdown document can trigger an overly large response.
Patches
0.17.0 contains https://github.com/kivikakk/comrak/commit/70f97f3ea4eae30ffbd1b94c764a3de2f1c41d2a, which limits reference output to a 100Kb maximum.
Workarounds
n/a
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | comrak | all versions | 0.17.0cargo update -p comrak --precise 0.17.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for comrak, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update comrak to 0.17.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xxmq-4vph-956w 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 GHSA-xxmq-4vph-956w can be triaged on real exposure rather than presence alone.
Tailored to GHSA-xxmq-4vph-956w. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-xxmq-4vph-956w in your dependencies?
O3 Security finds GHSA-xxmq-4vph-956w across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.