GHSA-2m96-52r3-2f3g is a medium-severity (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in fugit. A fix is available for fugit — see the affected versions and patch details below.
fugit parse and parse_nat stall on lengthy input
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-2m96-52r3-2f3g.
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-2m96-52r3-2f3g 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 377,166 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
fugitReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The fugit "natural" parser, that turns "every wednesday at 5pm" into "0 17 * * 3", accepted any length of input and went on attempting to parse it, not returning promptly, as expected. The parse call could hold the thread with no end in sight.
Fugit dependents that do not check (user) input length for plausability are impacted.
Patches
Problem was reported in #104 and the fix was released in fugit 1.11.1
Workarounds
By making sure that Fugit.parse(s), Fugit.do_parse(s), Fugit.parse_nat(s), Fugit.do_parse_nat(s), Fugit::Nat.parse(s), and Fugit::Nat.do_parse(s) are not fed strings too long. 1000 chars feels ok, while 10_000 chars makes it stall.
In fewer words, making sure those fugit methods are not fed unvetted input strings.
References
gh-104
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | fugit | all versions | 1.11.1bundle update fugit --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fugit, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update fugit to 1.11.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2m96-52r3-2f3g 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-2m96-52r3-2f3g can be triaged on real exposure rather than presence alone.
Tailored to GHSA-2m96-52r3-2f3g. 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-2m96-52r3-2f3g in your dependencies?
O3 Security finds GHSA-2m96-52r3-2f3g across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.