CVE-2026-127099: Sssd: sssd: stack buffer overflow during rsa certificate-to-ssh key conversion
Noroxi assessment
Priority: Monitor (action score 23/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
- According to the record, no fixed version is available yet.
Low priority for now. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
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.
- Published
- Nov 12, 2026
- Updated
- Nov 12, 2026
- EPSS
- —
- CWE
- CWE-121
Report tools
Action score
23
Low priority for now.
- CVSS
- 23 / 40 · 5.9 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · —
CNA vs NVD score
- NVD
- 5.9
- CNA · redhat
- 5.9
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.
Red Hat Red Hat Enterprise Linux 10
- all versionsaffected
Red Hat Red Hat Enterprise Linux 6
- all versionsaffected
Red Hat Red Hat Enterprise Linux 7
- all versionsaffected
Red Hat Red Hat Enterprise Linux 8
- all versionsaffected
Red Hat Red Hat Enterprise Linux 9
- all versionsaffected
Red Hat Red Hat OpenShift Container Platform 4
- all versionsaffected
- all versionsaffected
Red Hat Red Hat OpenShift Container Platform 5
- all versionsaffected
Same product
red hat: all recordsOther highest-scoring records for the same primary product.
- CVE-2025-10230Samba: command injection in wins server hook script52Plan
- CVE-2026-4631Cockpit: cockpit: unauthenticated remote code execution due to ssh command-line argument injection44Plan
- CVE-2026-76578Ipa: freeipa: freeipa: unauthenticated ldap client can obtain administrator credentials via the self-managed-token aci39Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-127030Nov 12, 2026 · Freeradius: stack buffer overflow via unchecked eap-fast sessionticket length30Monitor
- ← EarlierCVE-2026-126831Nov 12, 2026 · Cpio: cpio: stack-based buffer overflow in write_out_tar_header() with long usernames/groupnames22Monitor
- Later →CVE-2026-127100Nov 12, 2026 · Sssd: sssd: local denial of service through unchecked oauth2 json code type in pam responder22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
Not on record for this CVE: EPSS history · patch commit or PR link · variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- none
- Integrity
- low · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- Low
- Availability impact
- High
Weakness class (CWE)
CWE-121 · Stack-based Buffer OverflowCVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log (1)
- Exploit maturity— → none
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References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.