CVE-2026-30922
pyasn1 is a generic ASN.1 library for Python.
Published Mar 18, 2026 · corrected/updated Sep 10, 2026 · pyasn1 pyasn1 · evidence confidence medium
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.3, the 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 ( ) or ( ) tags with "Indefinite Length" ( ) markers. This forces the decoder to recursively call itself until the Python interpreter crashes with a 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 ( ) does not mitigate this recursion issue. Version 0.6.3 fixes this specific issue.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-30922 is a high public vulnerability record for pyasn1 pyasn1. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether pyasn1 pyasn1 is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: pyasn1/pyasn1. Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 7.5. It is not currently listed in the CISA Known Exploited catalog. Weakness classes: CWE-674, CWE-835. Sources contributing to this record: cve_org, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Mar 18, 2026 · NIST NVD
Detected
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.3, the 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 ( ) or ( ) tags with "Indefinite Length" ( ) markers. This forces the decoder to recursively call itself until the
Sep 10, 2026 · NIST NVD
Updated
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.3, the 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 ( ) or ( ) tags with "Indefinite Length" ( ) markers. This forces the decoder to recursively call itself until the
Affected
- cpe pyasn1/pyasn1version unspecified
Sources
- CVE.orgVulnerability recordCVE-2026-30922
Official CVE identifier
cve.org - NIST NVDVulnerability recordCVE-2026-30922
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.3, the 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 thousa
nvd.nist.gov