CVE-2026-30922

Published: Mar 18, 2026 Last Modified: Mar 18, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,5
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high

Description

AI Translation Available

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.

674

Uncontrolled Recursion

Draft
Common Consequences
Security Scopes Affected:
Availability Confidentiality
Potential Impacts:
Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Read Application Data
Applicable Platforms
All platforms may be affected
View CWE Details
https://github.com/pyasn1/pyasn1/commit/25ad481c19fdb006e20485ef3fc2e5b3eff30ef0
https://github.com/pyasn1/pyasn1/security/advisories/GHSA-jr27-m4p2-rc6r