CVE-2022-4064 — dalli
Fix: petergoldstein/dalli@48d594dCVE-2022-4064 is a CWE-74 vulnerability in dalli. 1 public exploit reference exists, so weaponization risk is real. A fix is available for dalli — see the affected versions and patch details below.
Dalli Meta Protocol request_formatter.rb self.meta_set injection
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-4064.
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
dalliReal-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 vulnerability was found in Dalli up to 3.2.2. It has been classified as problematic. Affected is the function self.meta_set of the file lib/dalli/protocol/meta/request_formatter.rb of the component Meta Protocol Handler. The manipulation of the argument cas/ttl leads to injection. It is possible to launch the attack remotely. The complexity of an attack is rather high. The exploitability is told to be difficult. The exploit has been disclosed to the public and may be used. Upgrading to version 3.2.3 is able to address this issue. The patch is identified as 48d594dae55934476fec61789e7a7c3700e0f50d. It is recommended to upgrade the affected component.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | dalli | all versions | 3.2.3bundle update dalli --conservative |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for dalli, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update dalli to 3.2.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-4064 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-2022-4064 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-4064. 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-2022-4064 in your dependencies?
O3 Security finds CVE-2022-4064 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.