{"id":"UBUNTU-CVE-2026-119194","details":"pyasn1 is a generic ASN.1 library for Python. From 0.3.3 until 0.6.5, schemaless container decoding stores every decoded component's TagSet in a growing set even though only one-versus-multiple tag types must be distinguished. Attacker-controlled BER, CER, or DER input contains many distinct long tag IDs whose TagSet hashes collide. Each later set insertion compares against an increasing number of earlier colliding tags in ConstructedPayloadDecoderBase._decodeComponentsSchemaless, producing quadratic CPU work while decoded values and order remain valid. Repeated inputs can exhaust decoder CPU and reduce service availability. This issue is fixed in version 0.6.5.","modified":"2026-10-31T03:30:12.336929081Z","published":"2026-10-30T00:00:00Z","upstream":["CVE-2026-119194"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-119194"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-119194"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/commit/a36e3a3d067148d26197a6b7221fd0e2cde9cc86"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/pull/132"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/releases/tag/v0.6.5"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-fm9c-5rcf-2q5p"}],"affected":[{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.1.4-0ubuntu1","0.1.7-1ubuntu1","0.1.7-1ubuntu2","0.1.7-1ubuntu2.1","0.1.7-1ubuntu2.1+esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.1.7-1ubuntu2.1+esm1","binary_name":"python-pyasn1"},{"binary_version":"0.1.7-1ubuntu2.1+esm1","binary_name":"python3-pyasn1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=esm-infra%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.1.8-2","0.1.9-1","0.1.9-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"pypy-pyasn1","binary_version":"0.1.9-1ubuntu0.1~esm1"},{"binary_name":"python-pyasn1","binary_version":"0.1.9-1ubuntu0.1~esm1"},{"binary_name":"python3-pyasn1","binary_version":"0.1.9-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.1.9-2","0.4.2-3","0.4.2-3ubuntu0.18.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"pypy-pyasn1","binary_version":"0.4.2-3ubuntu0.18.04.1~esm1"},{"binary_name":"python-pyasn1","binary_version":"0.4.2-3ubuntu0.18.04.1~esm1"},{"binary_version":"0.4.2-3ubuntu0.18.04.1~esm1","binary_name":"python3-pyasn1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.2-3","0.4.2-3build1","0.4.2-3ubuntu0.20.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.2-3ubuntu0.20.04.1~esm1","binary_name":"pypy-pyasn1"},{"binary_name":"python-pyasn1","binary_version":"0.4.2-3ubuntu0.20.04.1~esm1"},{"binary_name":"python3-pyasn1","binary_version":"0.4.2-3ubuntu0.20.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.8-1","0.4.8-1ubuntu0.1","0.4.8-1ubuntu0.2","0.4.8-1ubuntu0.3"],"ecosystem_specific":{"binaries":[{"binary_name":"pypy-pyasn1","binary_version":"0.4.8-1ubuntu0.3"},{"binary_name":"python3-pyasn1","binary_version":"0.4.8-1ubuntu0.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.8-4","0.4.8-4ubuntu0.1","0.4.8-4ubuntu0.2","0.4.8-4ubuntu0.3"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.8-4ubuntu0.3","binary_name":"python3-pyasn1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.3-1","0.6.4-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.6.4-1","binary_name":"python3-pyasn1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119194.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6.1-1","0.6.1-1build1","0.6.2-1","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