--- id: CVE-2026-23490 title: pyasn1 is a generic ASN.1 library for Python summary: >- pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.2, a Denial-of-Service issue has been found that leads to memory exhaustion from malformed RELATIVE-OID with excessive continuation octets. This vulnerability is fixed in 0.6.2. severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H' cwe: - CWE-770 vendor: pyasn1 product: pyasn1 affected: - pyasn1 < 0.6.2 - debian_linux = 11.0 patched: - pyasn1 0.6.2 published: '2026-01-16' updated: '2026-09-09' sourceUpdated: '2026-09-09T13:18:50.673' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23490' references: - url: >- https://github.com/pyasn1/pyasn1/commit/3908f144229eed4df24bd569d16e5991ace44970 label: security-advisories@github.com - url: 'https://github.com/pyasn1/pyasn1/releases/tag/v0.6.2' label: security-advisories@github.com - url: 'https://github.com/pyasn1/pyasn1/security/advisories/GHSA-63vm-454h-vhhq' label: security-advisories@github.com - url: 'https://lists.debian.org/debian-lts-announce/2026/02/msg00002.html' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://access.redhat.com/errata/RHSA-2026:13508' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:13512' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - 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url: 'https://access.redhat.com/errata/RHSA-2026:5606' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/security/cve/CVE-2026-23490' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2430472' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23490.json label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23490' - url: >- https://github.com/pyasn1/pyasn1/commit/be353d755f42ea36539b4f5053c652ddf56979a6 - url: 'https://github.com/advisories/GHSA-63vm-454h-vhhq' - url: 'https://github.com/pyasn1/pyasn1' - url: >- https://github.com/pyasn1/pyasn1/blob/0f07d7242a78ab4d129b26256d7474f7168cf536/pyasn1/codec/ber/decoder.py#L496 - url: >- https://github.com/pypa/advisory-database/tree/main/vulns/pyasn1/PYSEC-2026-1810.yaml - url: 'https://pypi.org/project/pyasn1' tags: - nvd - cve.org - exploit-available - osv - pip exploitAvailable: true ssvc: exploitation: poc automatable: 'yes' technicalImpact: partial timestamp: '2026-01-16T19:23:28.531270Z' epss: 0.00771 epssPercentile: 0.54195 ingestedAt: '2026-06-30T13:26:50.501Z' aliases: - GHSA-63vm-454h-vhhq - PYSEC-2026-1810 ecosystem: pip --- ## Overview pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.2, a Denial-of-Service issue has been found that leads to memory exhaustion from malformed RELATIVE-OID with excessive continuation octets. This vulnerability is fixed in 0.6.2. ## Affected - `pyasn1 < 0.6.2` - `debian_linux = 11.0` ## Remediation Upgrade past the affected range: - `pyasn1 0.6.2` ## Package advisory (CVE-2026-23490) Affected packages: - `pyasn1 >= 0.6.1, < 0.6.2` Patched in: - `pyasn1 0.6.2` Source: https://osv.dev/vulnerability/GHSA-63vm-454h-vhhq