# CVE-2026-104043: SSSD integer underflow in NSS responder packet parsing

Source: https://junglewise.ai/threats/cve-2026-104043-a-flaw-was-found-in-sssd-a-local-attacker-with-access-to-the  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-06. Updated: 2026-10-06  
License: CC BY 4.0 with a link back

CVE-2026-104043 · Severity: medium · CVSS 5.5 · Published 2026-10-06

SSSD is a system service that manages user identity and authentication across networks. A local attacker can craft a malicious network request to SSSD's identity service socket, causing it to crash and temporarily preventing user authentication and group resolution on affected systems. No data is exposed or accounts compromised, but the denial of service affects all users of the system.

Technologies: [Red Hat SSSD](https://junglewise.ai/threats/technologies/red-hat-sssd). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-104043 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-104043 being exploited in the wild.

**How severe is CVE-2026-104043?** Medium severity, with a CVSS score of 5.5, published 6 October 2026.

**Which products and versions are affected?** Red Hat SSSD.

**Is there a fix for CVE-2026-104043?** 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-2026-104043 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-104043?** Check whether you run Red Hat 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

An integer underflow in the NSS responder's packet parsing logic allows a local attacker to send a specially crafted request with an undersized packet header, triggering an out-of-bounds memory read. The attack requires local access to the NSS UNIX domain socket and low privilege level; exploitation causes the responder process to crash, denying service to identity and group resolution operations. The vulnerability is CWE-125 (out-of-bounds read) with no code execution or privilege escalation possible.

## Affected products

- Red Hat SSSD

## Timeline

- 2026-10-06: 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-2026-104043](https://access.redhat.com/security/cve/CVE-2026-104043)

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