CVE-2023-22795 — actionpack
CVE-2023-22795 is a Uncontrolled Resource Consumption vulnerability in actionpack. A fix is available for actionpack — see the affected versions and patch details below.
ReDoS based DoS vulnerability in Action Dispatch
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.
Real-World Exposure
actionpack💎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
A regular expression based DoS vulnerability in Action Dispatch <6.1.7.1 and <7.0.4.1 related to the If-None-Match header. A specially crafted HTTP If-None-Match header can cause the regular expression engine to enter a state of catastrophic backtracking, when on a version of Ruby below 3.2.0. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability All users running an affected release should either upgrade or use one of the workarounds immediately.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | actionpack | ≥ 4.0.0.beta1&&< 6.1.7.1 | 6.1.7.1bundle update actionpack --conservative |
| 💎RubyGems | actionpack | ≥ 7.0.0&&< 7.0.4.1 | 7.0.4.1bundle update actionpack --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for actionpack, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update actionpack to 6.1.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-22795 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 CVE-2023-22795 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-22795. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Satellite 6.14 for RHEL 8 | rubygem-actionpack-0:6.1.7.3-1.el8sat | RHSA-2023:6818 |
Frequently Asked Questions
Is CVE-2023-22795 in your dependencies?
O3 Security finds CVE-2023-22795 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.