How severe is CVE-2022-1941?

CVE-2022-1941 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2022-1941?

CVE-2022-1941 affects the following packages: protobuf (PyPI), protobuf (PyPI), protobuf (PyPI), protobuf (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2022-1941?

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.

How do I detect CVE-2022-1941 in my PyPI dependencies?

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.

How do I mitigate CVE-2022-1941 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2022-1941 actively exploited in the wild?

No public exploit code has been indexed for CVE-2022-1941 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2022-1941?

CVE-2022-1941 has an EPSS (Exploit Prediction Scoring System) score of 1.5%, placing it in the 74th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2022-1941?

CVE-2022-1941 is classified as CWE-1286 (CWE-1286). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2022-1941 published, and has it been updated?

CVE-2022-1941 was published on September 22, 2022 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

HIGH severity

CVE-2022-1941 — protobuf

HIGH

CVE-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

Also known asGHSA-8gq9-2x98-w8hfPYSEC-2026-899

Published

Sep 22, 2022

Updated

Oct 28, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Nov 3, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

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

via FIRST.org ↗

1.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs74th percentile — riskier than 74% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

4 pkgs affected

🐍protobuf🐍protobuf🐍protobuf🐍protobuf

Real-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

Summary

A message parsing and memory management vulnerability in ProtocolBuffer’s C++ and Python implementations can trigger an out of memory (OOM) failure when processing a specially crafted message, which could lead to a denial of service (DoS) on services using the libraries.

Reporter: ClusterFuzz

Affected versions: All versions of C++ Protobufs (including Python) prior to the versions listed below.

Severity & Impact

As scored by google
Medium 5.7 - CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Asscored byt NIST
High 7.5 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A small (~500 KB) malicious payload can be constructed which causes the running service to allocate more than 3GB of RAM.

Proof of Concept

For reproduction details, please refer to the unit test that identifies the specific inputs that exercise this parsing weakness.

Mitigation / Patching

Please update to the latest available versions of the following packages:

protobuf-cpp (3.18.3, 3.19.5, 3.20.2, 3.21.6)
protobuf-python (3.18.3, 3.19.5, 3.20.2, 4.21.6)

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`protobuf`	all versions	3.18.3`pip install --upgrade 'protobuf==3.18.3'`
🐍PyPI	`protobuf`	≥ 3.19.0&&< 3.19.5	3.19.5`pip install --upgrade 'protobuf==3.19.5'`
🐍PyPI	`protobuf`	≥ 3.20.0&&< 3.20.2	3.20.2`pip install --upgrade 'protobuf==3.20.2'`
🐍PyPI	`protobuf`	≥ 4.0.0&&< 4.21.6	4.21.6`pip install --upgrade 'protobuf==4.21.6'`

Affected Products

4 products · 11 configurations

debian linuxdebian

1 version

10.0

fedorafedoraproject

2 versions

3637

Application

protobuf-cppgoogle

≥ 3.21.0 && < 3.21.6

range

Application

protobuf-pythongoogle

≥ 4.0.0 && < 4.21.6

range

Detection & mitigation playbook

Open-source dependency

Detect
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
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

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.

Red HatModerate

Product	Fixed in	Advisory
Red Hat Enterprise Linux 9	`protobuf-0:3.14.0-16.el9`	RHSA-2025:7138

Frequently Asked Questions

### Summary A message parsing and memory management vulnerability in ProtocolBuffer’s C++ and Python implementations can trigger an out of memory (OOM) failure when processing a specially crafted message, which could lead to a denial of service (DoS) on services using the libraries. Reporter: [ClusterFuzz](https://google.github.io/clusterfuzz/) Affected versions: All versions of C++ Protobufs (including Python) prior to the versions listed below. ### Severity & Impact As scored by google **Medium 5.7** - [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H](https://www.first.org/cvss/calculator

O3 Security · Impact-Aware SCA

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