RHSA-2026:19042

Vulnerability from csaf_redhat - Published: 2026-05-19 13:25 - Updated: 2026-05-19 21:27
Summary
Red Hat Security Advisory: python-jwcrypto security update
Severity
Low
Notes
Topic: An update for python-jwcrypto is now available for Red Hat Enterprise Linux 10. Red Hat Product Security has rated this update as having a security impact of Low. 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): * JWCrypto: python-cryptography: python: JWCrypto: Memory exhaustion via crafted compressed JWE tokens (CVE-2026-39373) 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-2026-39373

A flaw was found in JWCrypto, a Python library for JSON Web Key (JWK), JSON Web Signature (JWS), and JSON Web Encryption (JWE) specifications. An unauthenticated attacker can exploit this vulnerability by sending specially crafted JWE tokens that use ZIP compression. While the input token size is limited, the decompressed output size is not validated, allowing an attacker to cause excessive memory consumption. This can lead to memory exhaustion on affected systems, resulting in a Denial of Service (DoS).

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-10.2.Z:python-jwcrypto-0:1.5.6-5.el10_2.src —
Vendor Fix fix
Unresolved product id: AppStream-10.2.Z:python3-jwcrypto-0:1.5.6-5.el10_2.noarch —
Vendor Fix fix
Threats
Impact Low
References
To clipboard 

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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