Out-of-bounds write in SSSD NFS idmap plugin enables denial of service
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · High
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
SSSD's NFS idmap plugin in Red Hat Enterprise Linux 6, 7, 8, 9 and 10 and in Red Hat OpenShift Container Platform 4 and 5 fails to abort when a cached user or group name exceeds the destination buffer, causing an out-of-bounds write (CWE-787). A local user with low privileges can trigger it by requesting identity lookups that resolve to oversized cached entries. The main impact is denial of service by crashing the identity mapping service, and adjacent process memory may also be corrupted.
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
Description from the CNA
A flaw was found in SSSD's NFS idmap plugin. When retrieving cached user or group names, the plugin detects if an entry exceeds the destination buffer size but fails to abort before copying data. A local attacker can trigger this vulnerability by requesting identity lookups that resolve to oversized cached entries, resulting in an out-of-bounds write. This flaw primarily leads to a Denial of Service (DoS) by crashing the identity mapping service, and may also corrupt adjacent process memory.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 5 | — | — | No fix listed | CNA |
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 5 VendorRed Hat Affected — Fixed in — No fix listed CNA
CPE names CNA · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:/a:redhat:enterprise_linux:10 | 10 | — | Red Hat |
| cpe:/o:redhat:rhel_els:6 | 6 | — | Red Hat |
| cpe:/o:redhat:rhel_els:7 | 7 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:8 | 8 | — | Red Hat |
| cpe:/a:redhat:enterprise_linux:9 | 9 | — | Red Hat |
| cpe:/a:redhat:openshift:4 | 4 | — | Red Hat |
| cpe:/a:redhat:openshift:5 | 5 | — | Red Hat |
- cpe:/a:redhat:enterprise_linux:10 Versions 10 — ·Red Hat
- cpe:/o:redhat:rhel_els:6 Versions 6 — ·Red Hat
- cpe:/o:redhat:rhel_els:7 Versions 7 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:8 Versions 8 — ·Red Hat
- cpe:/a:redhat:enterprise_linux:9 Versions 9 — ·Red Hat
- cpe:/a:redhat:openshift:4 Versions 4 — ·Red Hat
- cpe:/a:redhat:openshift:5 Versions 5 — ·Red Hat
Remediation
The sources list no fixed version for Red Hat Enterprise Linux 6, 7, 8, 9 and 10, or for Red Hat OpenShift Container Platform 4 and 5. Red Hat's plan is no fix planned for Red Hat Enterprise Linux 6 and none available for the other listed products.
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-06 Threatist record created from CVE-2026-104036
- 2026-10-06 Alias added: GHSA-95ww-m774-j7x2
- 2026-10-06 Affected versions changed · Red Hat
- 2026-10-06 CVSS score added · Red Hat
- 2026-10-06 CISA SSVC decision points changed
- 2026-10-06 Priority changed: MEDIUM → LOW
- 2026-11-05 Affected versions changed · CNA
- 2026-11-05 Affected versions changed · Red Hat
References
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Sources
- CVE-2026-104036 · CVE Program
- CVE-2026-104036 · NVD
- FIRST EPSS
- GHSA-95ww-m774-j7x2 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-104036 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences