CVE-2026-0994

Denial of Service in Python Protobuf

HIGH
7.5
CVSS Score
Published: January 23, 2026 at 02:55 PM UTC
Updated: September 1, 2026 at 03:31 PM UTC
2 products affected across 2 vendorsProtobufProtobuf

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 33.4
v ≤ 33.4

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (21)

PatchVendor Advisory
Source: cverecord
https://github.com/protocolbuffers/protobuf/pull/25239
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:16174
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3059
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3094
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3095
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3097
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3218
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:3219

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHredhat-SADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-674

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