Description
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER, CER, and DER decoders process OBJECT IDENTIFIER and RELATIVE-OID values in quadratic time relative to the number of arcs, so a small crafted payload containing an OID with many arcs consumes excessive CPU per decode() call and can deny service to applications that decode untrusted ASN.1 data. The corresponding encoders have the same quadratic behavior when an application re-encodes previously decoded attacker-supplied values. This issue is fixed in version 0.6.4.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| pyasn1 | pyasn1 | < 0.6.4 | — |
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 | pyasn1 | 0.6.4-1 | — |
| Debian 13 | pyasn1 | 0.6.1-1+deb13u3 | — |
| Debian 12 | pyasn1 | 0.4.8-3+deb12u3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | pyasn1 | 0.6.4-1ubuntu0.1 | USN-9011-1 |
| Ubuntu 26.04 LTS | pyasn1 | 0.6.3-1ubuntu0.1 | USN-9011-1, USN-8712-1 |
| Ubuntu 24.04 LTS | pyasn1 | 0.4.8-4ubuntu0.3 | USN-9011-1, USN-8712-1 |
| Ubuntu 22.04 LTS | pyasn1 | 0.4.8-1ubuntu0.3 | USN-9011-1, USN-8712-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | pyasn1 | 0.4.2-3ubuntu0.20.04.1~esm2 | USN-9011-1 |
| Ubuntu Pro 18.04 LTS | pyasn1 | 0.4.2-3ubuntu0.18.04.1~esm2 | USN-9011-1 |
| Ubuntu Pro 16.04 LTS | pyasn1 | 0.1.9-1ubuntu0.1~esm2 | USN-9011-1 |
| Ubuntu Pro 14.04 LTS | pyasn1 | 0.1.7-1ubuntu2.1+esm2 | USN-9011-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | jaeger | 2.19.0-1.1.hum1 | RHSA-2026:40236 |
| Red Hat Ansible Automation Platform Inside 2 | receptor +1 | 1.6.7-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform Developer 2 | automation-controller +1 | 4.7.15-2.el9ap | RHSA-2026:50336 |
| Red Hat Ansible Automation Platform Developer 2 | receptor +1 | 1.6.7-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Ansible Automation Platform 2 | automation-controller +3 | 4.7.15-2.el9ap | RHSA-2026:50336 |
| Red Hat Ansible Automation Platform 2 | automation-controller-venv-tower | 4.6.31-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | automation-eda-controller +4 | 1.1.21-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | automation-gateway-proxy +1 | 2.5.10-7.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | python3.12-aiohttp | 3.14.1-2.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | python3.12-daphne | 4.2.2-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | python3.12-pillow | 12.3.0-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | python3.12-pyasn1 | 0.6.4-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2 | receptor +1 | 1.6.7-1.el8ap | RHSA-2026:50336, RHSA-2026:50319 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES 15 SP5 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES 15 SP4 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES 3 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | python-pyasn1 | 0.6.1-160000.5.1 | SUSE-SU-2026:22830-1 |
| SLES for SAP 15 SP6 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES for SAP 15 SP5 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES for SAP 15 SP4 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLES 16.0 | python-pyasn1 | 0.6.1-160000.5.1 | SUSE-SU-2026:22830-1 |
| SLE Micro 6.2 | python-pyasn1 | 0.6.1-160000.5.1 | SUSE-SU-2026:22765-1 |
| SLE Micro 6.1 | python-pyasn1 | 0.5.0-slfo.1.1_4.1 | SUSE-SU-2026:23167-1 |
| SLE Micro 6.0 | python-pyasn1 | 0.5.0-5.1 | SUSE-SU-2026:23006-1 |
| SLE HPC 15 SP5 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
| SLE HPC 15 SP4 | python-pyasn1 | 0.5.0-150400.12.16.1 | SUSE-SU-2026:3238-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-pyasn1 | 0.6.4-1.1 | openSUSE-SU-2026:11318-1 |
| openSUSE Leap 16.0 | python-pyasn1 | 0.6.1-160000.5.1 | openSUSE-SU-2026:21392-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | python3-pyasn1 +2 | 0.4.8-4.amzn2023.0.5 | ALAS2023-2026-2000 |
| Amazon Linux 2 | python2-pyasn1 +3 | 0.1.9-7.amzn2.0.5 | ALAS2-2026-3836 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-pyasn1 | 0.4.8-3 | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | airflow-3 | 3.3.0-r4 | — |
| Wolfi rolling | datadog-agent-7.72-core-integrations | No fix yet | — |
| Wolfi rolling | datadog-agent-7.73-core-integrations | 7.73.3-r23 | — |
| Wolfi rolling | k8s-sidecar | 2.9.0-r0 | — |
| Wolfi rolling | kserve +1 | 0.20.0-r7 | — |
| Wolfi rolling | kserve-storage-controller | 0.19.0-r5 | — |
| Wolfi rolling | kubeflow-jupyter-web-app | 1.10.0-r23 | — |
| Wolfi rolling | kubeflow-pipelines-apiserver | 2.17.0-r4 | — |
| Wolfi rolling | kubeflow-pipelines-metadata-writer-compat | 2.17.2-r4 | — |
| Wolfi rolling | kubeflow-pipelines-visualization-server | 2.17.0-r1 | — |
| Wolfi rolling | kubeflow-profile-controller | 1.10.0-r36 | — |
| Wolfi rolling | kubeflow-volumes-web-app | 1.10.0-r22 | — |
| Wolfi rolling | mitmproxy | 12.2.3-r4 | — |
| Wolfi rolling | py3-cassandra-medusa | 0.29.1-r1 | — |
| Wolfi rolling | superset-6.0 | 6.0.0-r15 | — |
| Wolfi rolling | superset-6.1 | 6.1.0-r5 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | pyasn1 | < 0.6.4 | 0.6.4 | GHSA-8ppf-4f7h-5ppj |
Advisories 14
- USN-9011-1 pyasn1 vulnerabilities Ubuntu Security Notices (USN) · Nov 11, 2026
- RHSA-2026:50319 Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.5 Product Security and Bug Fix Update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:50336 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
- RHSA-2026:40236 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- USN-8712-1 pyasn1 vulnerabilities Ubuntu Security Notices (USN) · Sep 2, 2026
- SUSE-SU-2026:23167-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Aug 22, 2026
- SUSE-SU-2026:23006-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Aug 12, 2026
- ALAS2-2026-3836 Important: python-pyasn1 security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Aug 4, 2026
- ALAS2023-2026-2000 Important: python-pyasn1 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 4, 2026
- SUSE-SU-2026:3238-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22830-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:21392-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Jul 24, 2026
- SUSE-SU-2026:22765-1 Security update for python-pyasn1 SUSE / openSUSE Security Updates · Jul 23, 2026
- openSUSE-SU-2026:11318-1 python313-pyasn1-0.6.4-1.1 on GA media SUSE / openSUSE Security Updates · Jul 21, 2026