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Medium ALAS2-2026-3215 1 CVE

Moderate: python-pyasn1 security update (Amazon Linux 2)

Published Mar 30, 2026 · Updated Apr 1, 2026

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-30922: 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.

Fixed packages 4

ReleasePackageFixed in
Amazon Linux · 2 python2-pyasn1 0:0.1.9-7.amzn2.0.4
Amazon Linux · 2 python2-pyasn1-modules 0:0.1.9-7.amzn2.0.4
Amazon Linux · 2 python3-pyasn1 0:0.1.9-7.amzn2.0.4
Amazon Linux · 2 python3-pyasn1-modules 0:0.1.9-7.amzn2.0.4

Vulnerabilities 1

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-30922.html