CVE-2026-0994 (GCVE-0-2026-0994)

Vulnerability from cvelistv5 – Published: 2026-01-23 14:55 – Updated: 2026-01-30 14:28
VLAI?
Title
Denial of Service in Python Protobuf
Summary
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 RecursionError.
Severity ?
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L
CWE
Assigner
References
Impacted products
Vendor Product Version
Python Protobuf Affected: <=v33.4 (custom)
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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