CVE-2026-6245

Publication date 15 April 2026

Last updated 6 June 2026


Ubuntu priority

Cvss 3 Severity Score

5.5 · Medium

Score breakdown

Description

A flaw was found in the System Security Services Daemon (SSSD). The pam_passkey_child_read_data() function within the PAM passkey responder fails to properly handle raw bytes received from a pipe. Because the data is treated as a NUL-terminated C string without explicit termination, it results in an out-of-bounds read when processed by functions like snprintf(). A local attacker could potentially trigger this vulnerability by initiating a crafted passkey authentication request, causing the SSSD PAM responder to crash, resulting in a local Denial of Service (DoS).

Read the notes from the security team

Status

Package Ubuntu Release Status
sssd 26.04 LTS resolute
Fixed 2.12.0-1ubuntu5.1
25.10 questing
Fixed 2.10.1-2ubuntu5.2
24.04 LTS noble
Fixed 2.9.4-1.1ubuntu6.5
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected

Notes


mdeslaur

introduced in 2.9.0 by: https://github.com/SSSD/sssd/commit/c76ba343b783718468a3a108346d424f9a70eb76

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
sssd

Severity score breakdown

Parameter Value
Base score 5.5 · Medium
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

Other references


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