{"id":"CVE-2026-30922","aliases":["GHSA-jr27-m4p2-rc6r","PYSEC-2026-2263"],"url":"https://o3.security/vulnerability/CVE-2026-30922","summary":"pyasn1 Vulnerable to Denial of Service via Unbounded Recursion","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.","published":"2026-03-18T02:29:45.857Z","modified":"2026-08-07T03:30:25.742687028Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00803,"percentile":0.53215,"asOf":"2026-08-06"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"pyasn1","fixedVersion":"0.6.3"}],"fix":{"url":"https://github.com/pyasn1/pyasn1/commit/25ad481c19fdb006e20485ef3fc2e5b3eff30ef0","label":"pyasn1/pyasn1@25ad481"},"references":[{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2026/03/20/4"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2026/05/msg00001.html"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-30922.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:10184"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:12176"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13508"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13512"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13545"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13553"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13902"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13916"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:13917"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:14020"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:16009"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:17083"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:17611"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19138"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19355"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19375"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19712"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:20588"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22131"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22132"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22133"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22134"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22135"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22969"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22970"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:22987"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24761"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24762"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:37275"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:41928"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6309"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6568"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6720"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6912"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6926"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:8437"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-30922"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30922.json"},{"type":"ADVISORY","url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-jr27-m4p2-rc6r"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-30922"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2448553"},{"type":"FIX","url":"https://github.com/pyasn1/pyasn1/commit/25ad481c19fdb006e20485ef3fc2e5b3eff30ef0"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T03:30:25.742687028Z"}}