Description
MessagePack is the serializer implementation for Python msgpack.org. Prior to 1.2.1, there is an Out-of-bounds read/crash on Unpacker reuse after a caught error, potentially leading to a DoS attack. If the Unpacker is used repeatedly after an error occurs, the process may crash with a SEGV. This issue has been fixed in version 1.2.1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| msgpack | msgpack-python | < 1.2.1 | — |
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 | python-msgpack | 1.1.2-3 | — |
| Debian 13 | python-msgpack | No fix yet | — |
| Debian 12 | python-msgpack | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | python-pip +2 | No fix yet | — |
| Ubuntu 26.04 LTS | python-srsly +1 | No fix yet | — |
| Ubuntu 25.10 | python-pip +2 | No fix yet | — |
| Ubuntu 24.04 LTS | python-srsly +1 | No fix yet | — |
| Ubuntu 22.04 LTS | python-msgpack | No fix yet | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | python-msgpack | No fix yet | — |
| Ubuntu 18.04 LTS | python-msgpack | No fix yet | — |
| Ubuntu Pro 26.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 24.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 22.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 20.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 18.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 16.04 LTS | python-pip | No fix yet | — |
| Ubuntu Pro 14.04 LTS | python-pip | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3113-1 |
| SLES 15 SP6 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:4443-1, SUSE-SU-2026:3113-1 |
| SLES 15 SP5 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SLES 15 SP4 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SLES 3 | python-msgpack | 1.0.7-150600.3.5.1 | SUSE-SU-2026:4443-1 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:4443-1, SUSE-SU-2026:3113-1 |
| SLES for SAP 15 SP5 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SLES for SAP 15 SP4 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SLE Micro 6.1 | python-msgpack | 1.0.5-slfo.1.1_2.1 | SUSE-SU-2026:23169-1 |
| SLE Micro 6.0 | python-msgpack | 1.0.5-2.1 | SUSE-SU-2026:22704-1 |
| SLE Micro 5.5 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3113-1 |
| SLE Micro 5.4 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3113-1 |
| SLE Micro 5.3 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3113-1 |
| SLE HPC 15 SP5 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SLE HPC 15 SP4 | python-msgpack | 0.5.6-150100.3.6.1 | SUSE-SU-2026:3932-1, SUSE-SU-2026:3113-1 |
| SUSE Manager Client Tools 12 | python-msgpack-python | 0.4.6-8.8.1 | SUSE-SU-2026:3297-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-msgpack | 1.2.1-1.1 | openSUSE-SU-2026:11586-1 |
| openSUSE Leap 16.0 | python-msgpack | 1.1.0-160000.3.1 | openSUSE-SU-2026:21239-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-msgpack | 1.0.5-3 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | msgpack | < 1.2.1 | 1.2.1 | GHSA-6v7p-g79w-8964 |
Advisories 8
- SUSE-SU-2026:4443-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Oct 5, 2026
- SUSE-SU-2026:3932-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Sep 10, 2026
- openSUSE-SU-2026:11586-1 python313-msgpack-1.2.1-1.1 on GA media SUSE / openSUSE Security Updates · Aug 26, 2026
- SUSE-SU-2026:23169-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Aug 22, 2026
- SUSE-SU-2026:3297-1 Security update for python-msgpack-python SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22704-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Jul 23, 2026
- SUSE-SU-2026:3113-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Jul 18, 2026
- openSUSE-SU-2026:21239-1 Security update for python-msgpack SUSE / openSUSE Security Updates · Jul 9, 2026