PatchTheCVECVE-2026-0994: A denial-of-service (DoS) vulnerability exists in google.protobuf.json_format.ParseDict() in Python, where the
CVE-2026-0994 is a high-severity flaw (CVSS 7.5) affecting protobuf. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A denial-of-service (DoS) vulnerability exists in google.protobuf.json_format.ParseDict() in Python, where the max_recursion_depth limit can be bypassed when parsing nested google.protobuf.Any messages. Due to missing recursion depth accounting inside the internal Any-handling logic, an attacker can supply deeply nested Any structures that bypass the intended recursion limit, eventually exhausting Python’s recursion stack and causing a Recursion
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.7% (top 47%) |
| CISA exploited list | No |
| Weakness | CWE-674 |
| Published | 2026-01-23 |
| Last modified | 2026-09-01 |
Last updated 2026-09-01 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-0994?
protobuf: upgrade to newer than 33.4. Exact commands for each OS are on this page.
Is CVE-2026-0994 being exploited?
CVE-2026-0994 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-0994 affect?
CVE-2026-0994 affects protobuf. Severity is high (CVSS 7.5). A denial-of-service (DoS) vulnerability exists in google.protobuf.json_format.ParseDict() in Python, where the max_recursion_depth limit can be bypassed when parsing nested google.protobuf.Any messages. Due to missing recursion depth accou
How urgent is CVE-2026-0994?
Priority 45/100. High severity; Remotely exploitable, no login, no user action
Software pages
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