Information Exposure Through Timing Discrepancy in oauthlib - CVE-2026-49265

Vulnerability identifier: #VU152413

CSH Severity: Medium

CVSS v4: 7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-49265

CWE-ID: CWE-208

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to obtain an access token and take over an account.

The vulnerability exists due to an observable timing discrepancy in the PKCE code verifier comparison functions when processing token endpoint requests. A remote attacker can send repeated requests and measure response times to obtain an access token and take over an account.

User interaction is required.

oauthlib
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Desktop 15
SUSE Manager Proxy
SUSE Manager Retail Branch Server
SUSE Manager Server
SUSE Linux Micro
Public Cloud Module
Python 3 Module
openSUSE Leap
python311-oauthlib

Install security update from vendor's website.

oauthlib - update to 3.3.2
python311-oauthlib - addressed in versions 3.2.2-150400.12.10.1, 3.2.2-159998.1.1

• https://github.com/oauthlib/oauthlib/security/advisories/GHSA-xpv3-w29h-x7cv

• Multiple vulnerabilities in oauthlib
• SUSE update for python-oauthlib
• SUSE update for python-oauthlib