CVE-2026-68743 Sssd: sssd: pam responder out-of-bounds read via unchecked auth_token_length in protocol v1

What is CVE-2026-68743?

CVE-2026-68743 is a medium-severity denial of service vulnerability in Redhat Enterprise Linux, published on 4 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A flaw was found in SSSD. The extract_authtok_v1() function in the PAM responder does not validate the auth_token_length field against the remaining buffer size before processing. A local attacker can exploit this via a crafted protocol v1 request to the PAM responder socket, causing an out-of-bounds read and process crash, resulting in a denial of service.

Weakness: CWE-125

Which versions are affected by CVE-2026-68743?

It affects 3 products.

Products include Fedoraproject Sssd, Redhat Enterprise Linux, Redhat Openshift Container Platform.

How do I fix CVE-2026-68743?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-68743 being exploited?

There is no known exploitation of CVE-2026-68743 in the wild and no public exploit code.

Other vulnerabilities in Redhat Enterprise Linux

• CVE-2022-4254 Other in SSSD High 8.8
• CVE-2012-3462 Auth bypass in sssd High 8.8
• CVE-2026-104048 Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation Medium 6.8
• CVE-2015-5292 Denial of service in n/a Medium 6.8
• CVE-2026-12610 Sssd: use-after-free crash in sssd' 'sssd_pam' process Medium 6.4

All Redhat Enterprise Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as CLSA-2026-1787314091, CLSA-2026-1787394253, CLSA-2026-1787394686, CLSA-2026-1788440142, CLSA-2026-1789478531, CLSA-2026-1789479226 and 7 more.