{"id":"UBUNTU-CVE-2026-59886","details":"pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the univ.Real type converted its mantissa, base, and exponent value to a Python float using exact big-integer exponentiation. A BER, CER, or DER encoded REAL value only a few bytes long can carry a very large exponent, causing float conversion through prettyPrint(), str(), comparison, arithmetic, int(), or an explicit float() call to consume excessive CPU and memory and hang applications that decode untrusted ASN.1 data and then print, log, or compare decoded objects. This issue is fixed in version 0.6.4.","modified":"2026-09-01T21:00:07.378517885Z","published":"2026-07-14T17:17:00Z","related":["USN-8712-1"],"upstream":["CVE-2026-59886"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-59886"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-59886"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-hm4w-wwcw-mr6r"},{"type":"REPORT","url":"https://github.com/pyasn1/pyasn1/releases/tag/v0.6.4"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8712-1"}],"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_name":"python3-pyasn1","binary_version":"0.1.7-1ubuntu2.1+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-59886.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-2026-59886.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_name":"python3-pyasn1","binary_version":"0.4.2-3ubuntu0.18.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-59886.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_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","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-2026-59886.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-1ubuntu0.3"}]}],"versions":["0.4.8-1","0.4.8-1ubuntu0.1","0.4.8-1ubuntu0.2"],"ecosystem_specific":{"binaries":[{"binary_name":"pypy-pyasn1","binary_version":"0.4.8-1ubuntu0.3"},{"binary_version":"0.4.8-1ubuntu0.3","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-2026-59886.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-4ubuntu0.3"}]}],"versions":["0.4.8-4","0.4.8-4ubuntu0.1","0.4.8-4ubuntu0.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"python3-pyasn1","binary_version":"0.4.8-4ubuntu0.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-59886.json"}},{"package":{"name":"pyasn1","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/pyasn1?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.3-1ubuntu0.1"}]}],"versions":["0.6.1-1","0.6.1-1build1","0.6.2-1","0.6.3-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.6.3-1ubuntu0.1","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-2026-59886.json"}}],"schema_version":"1.9.0","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"}]}