GHSA-8hqf-xjwp-p67v is a medium-severity (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in comrak. A fix is available for comrak — see the affected versions and patch details below.
Comrak vulnerable to quadratic runtime issues when parsing Markdown (GHSL-2023-047)
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-8hqf-xjwp-p67v.
EPSS Exploitation Probability
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
GHSA-8hqf-xjwp-p67v 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
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
A range of quadratic parsing issues from cmark/cmark-gfm are also present in Comrak. These can be used to craft denial-of-service attacks on services that use Comrak to parse Markdown.
Patches
0.17.0 contains fixes to known quadratic parsing issues.
Workarounds
n/a
References
- https://github.com/commonmark/cmark/issues/255
- https://github.com/commonmark/cmark/issues/389
- https://github.com/commonmark/cmark/issues/373
- https://github.com/commonmark/cmark/issues/299
- https://github.com/commonmark/cmark/issues/388
- https://github.com/commonmark/cmark/issues/284
- https://github.com/commonmark/cmark/issues/218
- https://github.com/commonmark/cmark/pull/232
- https://github.com/github/cmark-gfm/blob/c32ef78bae851cb83b7ad52d0fbff880acdcd44a/test/pathological_tests.py#L63-L65
- https://github.com/github/cmark-gfm/blob/c32ef78bae851cb83b7ad52d0fbff880acdcd44a/test/pathological_tests.py#L87-L89
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-8hqf-xjwp-p67v 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-8hqf-xjwp-p67v can be triaged on real exposure rather than presence alone.
Tailored to GHSA-8hqf-xjwp-p67v. 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-8hqf-xjwp-p67v in your dependencies?
O3 Security finds GHSA-8hqf-xjwp-p67v across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.