ESB-2026.3699
PUBLISHED
CVSS 6.699999809265137 MEDIUM
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AUSCERT External Security Bulletin Redistribution
ESB-2026.3699
USN-8173-1: polkit vulnerabilities
15 April 2026
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AUSCERT Security Bulletin Summary
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Product: polkit
Publisher: Ubuntu
Operating System: Ubuntu
Resolution: Patch/Upgrade
CVE Names: CVE-2026-4897 CVE-2025-7519
Original Bulletin:
https://ubuntu.com/security/notices/USN-8173-1
Comment: CVSS (Max): 6.7 CVE-2025-7519 (CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)
CVSS Source: Ubuntu
Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS (Max): 0.0% (2nd) CVE-2026-4897 2026-04-14
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USN-8173-1: polkit vulnerabilities
Publication date
14 April 2026
Overview
Several security issues were fixed in polkit.
Releases
25.10 24.04 LTS 22.04 LTS
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Open side navigation
Packages
o policykit-1 - framework for managing administrative policies and privileges
Details
It was discovered that polkit incorrectly handled nested elements in XML
policy files. If an administrator were tricked into installing a malicious
policy file, a remote attacker could possibly use this issue to cause
polkit to crash, resulting in a denial of service. ( CVE-2025-7519 )
Pavel Kohout discovered that the polkit polkit-agent-helper-1 utility
incorrectly handled long input. A local attacker could possibly use this
issue to cause polkit to crash, resulting in a denial of service.
( CVE-2026-4897 )
Update instructions
The problem can be corrected by updating your system to the following package
versions:
Ubuntu Release Package Version
25.10 questing polkitd - 126-2ubuntu0.1
24.04 LTS noble policykit-1 - 124-2ubuntu1.24.04.3
22.04 LTS jammy policykit-1 - 0.105-33ubuntu0.1
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References
o CVE-2026-4897
o CVE-2025-7519
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