CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:HCVE-2026-127099 Sssd: sssd: stack buffer overflow during rsa certificate-to-ssh key conversion
Medium (5.9) in red hat. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
A flaw was found in SSSD's conversion of X.509 certificate RSA public keys to SSH keys. Missing size checks before copying RSA components into fixed-size stack buffers can cause a stack buffer overflow. An attacker able to supply a certificate with oversized RSA components that passes the configured certificate checks can cause denial of service and corrupt SSH responder memory.
Severity
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 6th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-121 Stack-based Buffer Overflow
- Published
- Modified
- Assigned by
- redhat (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
Show the prompt
Explain CVE-2026-127099 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-127099?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-127099?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-127099 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Badge for a README or a site
An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:
[](https://cve.bz/cve/CVE-2026-127099)
HTML:
<a href="https://cve.bz/cve/CVE-2026-127099"><img src="https://cve.bz/cve/badge/CVE-2026-127099.svg" alt="CVE-2026-127099"></a>
Affected
- red hat:red hat enterprise linux 10
- red hat:red hat enterprise linux 6
- red hat:red hat enterprise linux 7
- red hat:red hat enterprise linux 8
- red hat:red hat enterprise linux 9
- red hat:red hat openshift container platform 4
- red hat:red hat openshift container platform 5
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 22.04:LTS, 24.04:LTS, 26.04:LTS and 4 more | sssd | no fix listed | UBUNTU-CVE-2026-127099 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.