Description
Any project that uses Protobuf Pure-Python backend to parse untrusted Protocol Buffers data containing an arbitrary number of recursive groups, recursive messages or a series of SGROUP tags can be corrupted by exceeding the Python recursion limit. This can result in a Denial of service by crashing the application with a RecursionError. We recommend upgrading to version =>6.31.1 or beyond commit 17838beda2943d08b8a9d4df5b68f5f04f26d901
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| protocolbuffers | Python-Protobuf | < 4.25.8, < 5.29.5, < 6.31.1 | 4.25.8 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | protobuf | 3.21.12-12 | — |
| Debian 13 | protobuf | 3.21.12-11+deb13u1 | — |
| Debian 12 | protobuf | 3.21.12-3+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | protobuf | 3.21.12-8.2ubuntu0.2 | USN-7629-1 |
| Ubuntu 22.04 LTS | protobuf | 3.12.4-1ubuntu7.22.04.4 | USN-7629-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | protobuf | 3.6.1.3-2ubuntu5.2+esm2 | USN-7629-2 |
| Ubuntu Pro 18.04 LTS | protobuf | 3.0.0-9.1ubuntu1.1+esm3 | USN-7629-2 |
| Ubuntu Pro 16.04 LTS | protobuf | 2.6.1-1.3ubuntu0.1~esm4 | USN-7629-2 |
| Ubuntu Pro 14.04 LTS | protobuf | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Ansible Automation Platform Inside 2 | receptor | 1.6.3-2.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform Developer 2 | python3.11-django | 4.2.27-2.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform Developer 2 | python3.11-urllib3 | 2.6.3-1.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform Developer 2 | receptor | 1.6.3-2.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform 2 | automation-controller-venv-tower | 4.7.8-1.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform 2 | python3.11-django | 4.2.27-2.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform 2 | python3.11-protobuf | 4.25.8-1.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform 2 | python3.11-urllib3 | 2.6.3-1.el9ap | RHSA-2026:1249 |
| Red Hat Ansible Automation Platform 2 | receptor | 1.6.3-2.el9ap | RHSA-2026:1249 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02311-1 |
| SLES 15 SP6 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02311-1 |
| SLES 15 SP5 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02310-1 |
| SLES 15 SP4 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02309-1 |
| SLES 15 SP3 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1 |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 3 | protobuf | 25.1-150600.16.13.1 | SUSE-SU-2025:02311-1 |
| SLES for SAP 16.0 | protobuf +1 | 28.3-160000.3.1 | SUSE-SU-2026:20907-1 |
| SLES for SAP 16.0 | python-protobuf | 5.28.3-160000.3.1 | SUSE-SU-2026:20907-1 |
| SLES 16.0 | protobuf +1 | 28.3-160000.3.1 | SUSE-SU-2026:20907-1 |
| SLES 16.0 | python-protobuf | 5.28.3-160000.3.1 | SUSE-SU-2026:20907-1 |
| SLE Micro 6.2 | protobuf | 28.3-160000.3.1 | SUSE-SU-2026:20753-1 |
| SLE Micro 6.1 | protobuf | 23.4-slfo.1.1_2.1 | SUSE-SU-2025:20672-1 |
| SLE Micro 6.0 | protobuf | 23.4-10.1 | SUSE-SU-2025:20514-1 |
| SLE Micro 5.5 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02310-1 |
| SLE Micro 5.4 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02309-1 |
| SLE Micro 5.3 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1, SUSE-SU-2025:02309-1 |
| SLE Micro 5.2 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1 |
| SLE Micro 5.1 | protobuf | 3.9.2-150200.4.27.1 | SUSE-SU-2025:3722-1 |
| SUSE Manager Server Module 4.3 | protobuf | 25.1-150400.9.16.1 | SUSE-SU-2025:02309-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | protobuf | 31.1-1.1 | openSUSE-SU-2025:15265-1 |
| openSUSE Leap 16.0 | protobuf +1 | 28.3-160000.3.1 | openSUSE-SU-2026:20390-1 |
| openSUSE Leap 16.0 | python-protobuf | 5.28.3-160000.3.1 | openSUSE-SU-2026:20390-1 |
| openSUSE Leap 15.6 | protobuf | 25.1-150600.16.13.1 | SUSE-SU-2025:02311-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | protobuf | 25.3-5 | — |
| Azure Linux 2 (CBL-Mariner) | protobuf | 3.17.3-4 | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | kserve +9 | 0.15.2-r2 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | protobuf | < 4.25.8 | 4.25.8 | GHSA-8qvm-5x2c-j2w7 |
| PyPI | protobuf | >= 5.26.0rc1, < 5.29.5 | 5.29.5 | GHSA-8qvm-5x2c-j2w7 |
| PyPI | protobuf | >= 6.30.0rc1, < 6.31.1 | 6.31.1 | GHSA-8qvm-5x2c-j2w7 |
| PyPI | protobuf | < 4.25.8 · >= 5.26.0rc1, < 5.29.5 · >= 6.30.0rc1, < 6.31.1 | 4.25.8, 5.29.5, 6.31.1 | PYSEC-2026-1806 |
Advisories 14
- RHSA-2026:1249 Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.6 Product Security and Bug Fix Update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- USN-7629-2 protobuf vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- WID-SEC-2025-1548 Red Hat OpenShift Container Platform: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Apr 29, 2026
- USN-7629-1 protobuf vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2026:20907-1 Security update for protobuf SUSE / openSUSE Security Updates · Apr 2, 2026
- openSUSE-SU-2026:20390-1 Security update for protobuf SUSE / openSUSE Security Updates · Mar 26, 2026
- SUSE-SU-2026:20753-1 Security update for protobuf SUSE / openSUSE Security Updates · Mar 25, 2026
- openSUSE-SU-2025:15265-1 libprotobuf-lite31_1_0-31.1-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20672-1 Security update for protobuf SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20514-1 Security update for protobuf SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02310-1 Security update for protobuf SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:02311-1 Security update for protobuf SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:02309-1 Security update for protobuf SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:3722-1 Security update for protobuf SUSE / openSUSE Security Updates · Feb 4, 2026