CVE-2026-104041
Sssd: sssd: denial of service via unbounded negative cache growth
A flaw was found in SSSD. An unprivileged local user can repeatedly request lookups for nonexistent entries through the Name Service Switch (NSS) responder. Because the negative cache does not limit the total number of stored entries and only removes expired records when an existing key is rechecked, the cache can grow without bound. This behavior can lead to memory exhaustion, resulting in a Denial of Service (DoS) as the responder becomes unresponsive or terminates.
Fixes and workarounds
Workaround
Set `entry_negative_timeout = 0` in the `[nss]` section of `/etc/sssd/sssd.conf` to disable non-permanent negative-cache insertions, then restart the SSSD service (for example, `systemctl restart sssd`) to apply the change. Note that restarting sssd briefly interrupts active authentication and identity lookups, and disabling the negative cache increases lookup traffic to identity backends for nonexistent entries. If responder memory growth is observed, the accumulated negative-cache state can be cleared through the existing operational clear path or by restarting the responder. Restricting untrusted local users also limits exposure on systems where the NSS responder socket is reachable by local users.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Red Hat Enterprise Linux 10 Red Hat sssd
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Red Hat sssd
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unknown |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat sssd
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat sssd
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat sssd
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4 Red Hat openshift/ose-rhel-coreos-8
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 5 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 5.5 medium |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | CNA: redhat |
Exploit evidence
- https://bugzilla.redhat.com/show_bug.cgi?id=2478864
exploit · ADP: CISA-ADP
References
- https://access.redhat.com/security/cve/CVE-2026-104041CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2478864CNA: redhat · issue-tracking, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2478864ADP: CISA-ADP · exploit
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.