RHSA-2026:4138

Vulnerability from csaf_redhat - Published: 2026-03-10 00:22 - Updated: 2026-07-21 10:06
Summary
Red Hat Security Advisory: python-pyasn1 security update
Severity
Important
Notes
Topic: An update for python-pyasn1 is now available for Red Hat Enterprise Linux 10.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Details: Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems. Security Fix(es): * pyasn1: pyasn1: Denial of Service due to memory exhaustion from malformed RELATIVE-OID (CVE-2026-23490) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2026-23490

A flaw was found in pyasn1, a generic ASN.1 library for Python. A remote attacker could exploit this vulnerability by sending a specially crafted RELATIVE-OID with excessive continuation octets. This input validation vulnerability leads to memory exhaustion, resulting in a Denial of Service (DoS) for the affected system.

7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-770 - Allocation of Resources Without Limits or Throttling
Affected products
Product Identifier Version Remediation
Unresolved product id: AppStream-10.0.Z.E2S:python-pyasn1-0:0.6.2-1.el10_0.1.src —
Vendor Fix fix
Unresolved product id: AppStream-10.0.Z.E2S:python3-pyasn1-0:0.6.2-1.el10_0.1.noarch —
Vendor Fix fix
Unresolved product id: AppStream-10.0.Z.E2S:python3-pyasn1-modules-0:0.6.2-1.el10_0.1.noarch —
Vendor Fix fix
Threats
Impact Important
References
To clipboard 

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            "integrityImpact": "NONE",
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      "title": "pyasn1: pyasn1: Denial of Service due to memory exhaustion from malformed RELATIVE-OID"
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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