CVE-2026-87853
sssd: A flaw was found in SSSD's IdP authentication provider
CVE-2026-87853 is fixed in 29 products on 1 platform, first by RHSA-2026:77534, released September 9, 2026. It is not reported as exploited. Patch Radar priority: High.
High
CVSS
7.5
moderate
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0033
26th percentile
A flaw was found in SSSD's IdP authentication provider. The eval_access_token_buf() function compares the OIDC subject identifier using strncmp() with the authenticated user's identifier length, performing a prefix comparison instead of an exact match. An attacker whose IdP identifier is a strict prefix of a target user's identifier can authenticate as the target user.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Linux | |||
| libipa_hbac · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libipa_hbac · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_autofs · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_autofs · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_certmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_certmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_idmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_idmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_nss_idmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_nss_idmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_nss_idmap-devel · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_nss_idmap-devel · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| libsss_sudo · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| libsss_sudo · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| python3-libipa_hbac · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| python3-libipa_hbac · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| python3-libsss_nss_idmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| python3-libsss_nss_idmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| python3-sss · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| python3-sss · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| python3-sss-murmur · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| python3-sss-murmur · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| python3-sssdconfig · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| python3-sssdconfig · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd · RHEL 10 | 2.12.0-3.el10_2.2 | RHSA-2026:77534 | Sep 9, 2026 |
| sssd · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd · rocky 10 | 0:2.12.0-3.el10_2.2 | RLSA-2026:77534 | Nov 7, 2026 |
| sssd-ad · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-ad · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-client · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-client · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-common · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-common · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-common-pac · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-common-pac · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-dbus · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-dbus · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-idp · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-idp · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-ipa · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-ipa · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-kcm · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-kcm · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-krb5 · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-krb5 · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-krb5-common · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-krb5-common · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-ldap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-ldap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-nfs-idmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-nfs-idmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-passkey · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-passkey · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-proxy · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-proxy · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-tools · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-tools · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
| sssd-winbind-idmap · almalinux 10 | 2.12.0-3.el10_2.2 | ALSA-2026:77534 | Oct 7, 2026 |
| sssd-winbind-idmap · ol 10 | 0:2.12.0-3.0.1.el10_2.2 | ELSA-2026-77534 | Oct 8, 2026 |
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