CVE-2024-26142
HIGHCVE-2024-26142 is a high-severity (CVSS 7.5) CWE-1333 vulnerability in actionpack. O3 Security confirms whether CVE-2024-26142 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Rails possible ReDoS vulnerability in Accept header parsing in Action Dispatch
Blast Radius
actionpackReal-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
Rails is a web-application framework. Starting in version 7.1.0, there is a possible ReDoS vulnerability in the Accept header parsing routines of Action Dispatch. This vulnerability is patched in 7.1.3.1. Ruby 3.2 has mitigations for this problem, so Rails applications using Ruby 3.2 or newer are unaffected.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | actionpack | ≥ 7.1.0&&< 7.1.3.1 | 7.1.3.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for actionpack. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update actionpack to 7.1.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-26142 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 pinpoints whether CVE-2024-26142 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2024-26142. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-26142 in your dependencies?
O3 detects CVE-2024-26142 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.