OESA-2026-1779 (CVE-2026-30922)

Vulnerability from osv_openeuler – Published: 2026-03-27 11:10 – Updated: 2026-08-06 11:10 – Source website
VLAI
Summary
python-pyasn1 security update
Details

Abstract Syntax Notation One (ASN.1) is a technology for exchanging structured data in a universally understood, hardware agnostic way. Many industrial, security and telephony applications heavily rely on ASN.1. The pyasn1 library implements ASN.1 support in pure-Python.

Security Fix(es):

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 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. The vulnerability exists in the indefLenValueDecoder, valueDecoder, and _decodeComponentsSchemaless functions, which recursively invoke the decoding callback decodeFun without passing a depth parameter or checking against a global MAX_ASN1_NESTING limit. Any service using pyasn1 to parse untrusted ASN.1 data (e.g., LDAP, SNMP, Kerberos, X.509 parsers) can be crashed remotely.(CVE-2026-30922)

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "noarch": [
          "python-pyasn1-help-0.5.1-3.oe2403.noarch.rpm",
          "python3-pyasn1-0.5.1-3.oe2403.noarch.rpm"
        ],
        "src": [
          "python-pyasn1-0.5.1-3.oe2403.src.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS",
        "name": "python-pyasn1",
        "purl": "pkg:rpm/openEuler/python-pyasn1\u0026distro=openEuler-24.03-LTS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.5.1-3.oe2403"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "Abstract Syntax Notation One (ASN.1) is a technology for exchanging structured data in a universally understood, hardware agnostic way. Many industrial, security and telephony applications heavily rely on ASN.1. The pyasn1 library implements ASN.1 support in pure-Python.\r\n\r\nSecurity Fix(es):\n\nThe `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 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. The vulnerability exists in the `indefLenValueDecoder`, `valueDecoder`, and `_decodeComponentsSchemaless` functions, which recursively invoke the decoding callback `decodeFun` without passing a `depth` parameter or checking against a global `MAX_ASN1_NESTING` limit. Any service using `pyasn1` to parse untrusted ASN.1 data (e.g., LDAP, SNMP, Kerberos, X.509 parsers) can be crashed remotely.(CVE-2026-30922)",
  "id": "OESA-2026-1779",
  "modified": "2026-08-06T11:10:48Z",
  "published": "2026-03-27T11:10:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1779"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-30922"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "python-pyasn1 security update",
  "upstream": [
    "CVE-2026-30922"
  ]
}



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