CVE-2022-1941 — protobuf
HIGHCVE-2022-1941 is a high-severity (CVSS 7.5) CWE-1286 vulnerability in protobuf. A fix is available for protobuf — see the affected versions and patch details below.
Out of Memory issue in ProtocolBuffers for cpp and python
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 CVE-2022-1941.
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
CVE-2022-1941 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 377,333 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
protobuf🐍protobuf🐍protobuf🐍protobufReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | protobuf | all versions | 3.18.3pip install --upgrade 'protobuf==3.18.3' |
| 🐍PyPI | protobuf | ≥ 3.19.0&&< 3.19.5 | 3.19.5pip install --upgrade 'protobuf==3.19.5' |
| 🐍PyPI | protobuf | ≥ 3.20.0&&< 3.20.2 | 3.20.2pip install --upgrade 'protobuf==3.20.2' |
| 🐍PyPI | protobuf | ≥ 4.0.0&&< 4.21.6 | 4.21.6pip install --upgrade 'protobuf==4.21.6' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for protobuf, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update protobuf to 3.18.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-1941 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-2022-1941 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-1941. 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 Enterprise Linux 9 | protobuf-0:3.14.0-16.el9 | RHSA-2025:7138 |
Frequently Asked Questions
Is CVE-2022-1941 in your dependencies?
O3 Security finds CVE-2022-1941 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.