{"id":"UBUNTU-CVE-2026-30922","details":"pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.3, the `pyasn1` library is vulnerable to a Denial of Service (DoS) attack caused by uncontrolled recursion when decoding ASN.1 data with deeply nested structures. An attacker can supply a crafted payload containing thousands of nested `SEQUENCE` (`0x30`) or `SET` (`0x31`) tags with \"Indefinite Length\" (`0x80`) markers. This forces the decoder to recursively call itself until the Python interpreter crashes with a `RecursionError` or consumes all available memory (OOM), crashing the host application. This is a distinct vulnerability from CVE-2026-23490 (which addressed integer overflows in OID decoding). The fix for CVE-2026-23490 (`MAX_OID_ARC_CONTINUATION_OCTETS`) does not mitigate this recursion issue. Version 0.6.3 fixes this specific issue.","modified":"2026-03-31T18:14:22.339620Z","published":"2026-03-18T04:17:00Z","related":["USN-8129-1","USN-8134-1"],"upstream":["CVE-2026-30922"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-30922"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-30922"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-jr27-m4p2-rc6r"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8129-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8134-1"}],"affected":[{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.1.7-1ubuntu2.1+esm1?arch=source&distro=esm-infra-legacy/trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.1.7-1ubuntu2.1+esm1"}]}],"versions":["0.1.4-0ubuntu1","0.1.7-1ubuntu1","0.1.7-1ubuntu2","0.1.7-1ubuntu2.1"],"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"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.1.9-1ubuntu0.1~esm1?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.1.9-1ubuntu0.1~esm1"}]}],"versions":["0.1.8-2","0.1.9-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.1.9-1ubuntu0.1~esm1","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"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.4.2-3ubuntu0.18.04.1~esm1?arch=source&distro=esm-infra/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.2-3ubuntu0.18.04.1~esm1"}]}],"versions":["0.1.9-2","0.4.2-3"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.2-3ubuntu0.18.04.1~esm1","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_name":"python3-pyasn1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.4.2-3ubuntu0.20.04.1~esm1?arch=source&distro=esm-infra/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.2-3ubuntu0.20.04.1~esm1"}]}],"versions":["0.4.2-3","0.4.2-3build1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.2-3ubuntu0.20.04.1~esm1","binary_name":"pypy-pyasn1"},{"binary_version":"0.4.2-3ubuntu0.20.04.1~esm1","binary_name":"python-pyasn1"},{"binary_version":"0.4.2-3ubuntu0.20.04.1~esm1","binary_name":"python3-pyasn1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.4.8-1ubuntu0.2?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-1ubuntu0.2"}]}],"versions":["0.4.8-1","0.4.8-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.8-1ubuntu0.2","binary_name":"pypy-pyasn1"},{"binary_version":"0.4.8-1ubuntu0.2","binary_name":"python3-pyasn1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/pyasn1@0.4.8-4ubuntu0.2?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-4ubuntu0.2"}]}],"versions":["0.4.8-4","0.4.8-4ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.8-4ubuntu0.2","binary_name":"python3-pyasn1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/pyasn1@0.6.1-1ubuntu0.2?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.1-1ubuntu0.2"}]}],"versions":["0.6.1-1","0.6.1-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.6.1-1ubuntu0.2","binary_name":"python3-pyasn1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-30922.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}