CVE-2026-0994Uncontrolled Recursion in Google Protobuf

Severity
8.2HIGHNVD
EPSS
0.0%
top 97.93%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedJan 23
Latest updateFeb 25

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.

CVSS vector

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

Affected Packages3 packages

PyPIgoogle/protobuf6.30.0rc16.33.5+1
NVDgoogle/protobuf33.4
CVEListV5python/protobuf<=v33.4

Patches

🔴Vulnerability Details

4
CVEList
Denial of Service in Python Protobuf2026-01-23
OSV
CVE-2026-0994: A denial-of-service (DoS) vulnerability exists in google2026-01-23
OSV
protobuf affected by a JSON recursion depth bypass2026-01-23
GHSA
protobuf affected by a JSON recursion depth bypass2026-01-23

📋Vendor Advisories

3
Ubuntu
Protocol Buffers vulnerability2026-02-25
Red Hat
python: protobuf: Protobuf: Denial of Service due to recursion depth bypass2026-01-23
Debian
CVE-2026-0994: protobuf - A denial-of-service (DoS) vulnerability exists in google.protobuf.json_format.Pa...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-0994 Impact, Exploitability, and Mitigation Steps | Wiz

💬Community

1
Bugzilla
CVE-2026-0994 python: protobuf: Protobuf: Denial of Service due to recursion depth bypass2026-01-23
CVE-2026-0994 — Uncontrolled Recursion in Google | cvebase