High 8.2Published Jan 23, 2026

CVE-2026-0994Denial of Service in Python Protobuf

Updated under an hour ago (Oct 26, 2026, 6:10 PM ET)

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It affects Python Protobuf and 10 other products. Add what you run to find out whether that includes you.

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Every CVE for Python Protobuf

Exploited in the last 30 days

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.

CVSS: 8.2 HIGH (v4.0, CNA)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
Weakness (CWE): CWE-674
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Google
NVD analysis: Modified
Record last updated: Sep 1, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Python Protobuf python:protobuf (from the name)	through 33.4	CNA record
Red Hat Red Hat Ansible Automation Platform 2.5 for RHEL 8 redhat:ansible_automation_platform	from 0:5.29.6-1.el8ap not affected	CISA ADP
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux	from 0:3.19.6-15.el10_1 not affected	CISA ADP
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support redhat:enterprise_linux_eus	from 0:3.19.6-11.el10_0.1 not affected	CISA ADP
Red Hat Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions redhat:rhel_e4s	from 0:3.14.0-9.el9_0.1 not affected	CISA ADP
Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support redhat:rhel_eus	from 0:3.14.0-13.el9_4.1 not affected	CISA ADP
Red Hat Red Hat AI Inference Server 3.2 redhat:ai_inference_server	from 1772160593 not affected	CISA ADP
Red Hat Red Hat AMQ Clients redhat:amq_clients	2023	CISA ADP
Red Hat Red Hat Hardened Images redhat:hummingbird	1	CISA ADP
Red Hat Red Hat OpenStack Platform 16.2 redhat:openstack	16.2	CISA ADP
1–10 of 11

References

References

https://github.com/protocolbuffers/protobuf/pull/25239	patch, vendor-advisory
https://access.redhat.com/errata/RHSA-2026:16174
https://access.redhat.com/errata/RHSA-2026:3059
https://access.redhat.com/errata/RHSA-2026:3094
https://access.redhat.com/errata/RHSA-2026:3095
https://access.redhat.com/errata/RHSA-2026:3097
https://access.redhat.com/errata/RHSA-2026:3218
https://access.redhat.com/errata/RHSA-2026:3219
https://access.redhat.com/errata/RHSA-2026:3220
https://access.redhat.com/errata/RHSA-2026:3461
1–10 of 21

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.