# CVE-2026-68743: SSSD out-of-bounds read in PAM responder

Source: https://junglewise.ai/threats/cve-2026-68743-sssd-out-of-bounds-read-in-pam-responder  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-04. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-68743 · Severity: medium · CVSS 5.5 · Published 2026-08-04

SSSD is a system service that handles user authentication on Linux systems. A flaw in its PAM responder allows a local attacker to send a specially crafted request that causes the service to read memory beyond its buffer boundaries, crashing the authentication daemon. This results in denial of service, potentially preventing legitimate users from logging in to systems managed by SSSD.

Technologies: [SSSD Project SSSD](https://junglewise.ai/threats/technologies/sssd). Vendors: [SSSD Project](https://junglewise.ai/threats/vendors/sssd-project).

## Quick answers

**Is CVE-2026-68743 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-68743 being exploited in the wild.

**How severe is CVE-2026-68743?** Medium severity, with a CVSS score of 5.5, published 4 August 2026.

**Which products and versions are affected?** SSSD Project SSSD.

**Is there a fix for CVE-2026-68743?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-68743 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-68743?** Check whether you run SSSD Project SSSD. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an out-of-bounds read (CWE-125) in the extract_authtok_v1() function within SSSD's PAM responder. The function fails to validate the auth_token_length field against the remaining buffer size before processing. A local attacker who can connect to the SSSD PAM responder Unix socket can send a crafted protocol v1 request to trigger an out-of-bounds read, causing a process crash and denial of service. The stock PAM client uses protocol v3 and is unaffected; this path is only exploitable via direct socket access with a malicious v1 request.

## Affected products

- SSSD Project SSSD

## Timeline

- 2026-08-04: disclosed

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-68743](https://access.redhat.com/security/cve/CVE-2026-68743)

## Related threats

- [SSSD PAM responder NULL pointer dereference](https://junglewise.ai/threats/cve-2026-127101-a-flaw-was-found-in-sssd-s-pam-responder-a-local-attacker-can)
- [sssd responder denial of service via file descriptor exhaustion](https://junglewise.ai/threats/cve-2026-88252-a-flaw-was-found-in-sssd-a-local-user-can-cause-a-denial-of)
- [SSSD NFS idmap plugin out-of-bounds write](https://junglewise.ai/threats/cve-2026-104036-a-flaw-was-found-in-sssd-s-nfs-idmap-plugin-when-retrieving)
- [SSSD Kerberos Credential Manager memory exhaustion denial of service](https://junglewise.ai/threats/cve-2026-104035-a-flaw-was-found-in-sssd-an-issue-in-the-kerberos-credential)
- [SSSD LDAP shadow expiration bypass](https://junglewise.ai/threats/cve-2026-104033-a-flaw-was-found-in-sssd-when-configured-to-enforce-account)