CVE-2026-6245 Red Hat CVE debrief

Who should care

System administrators and security teams responsible for Red Hat Enterprise Linux and OpenShift Container Platform systems should assess and mitigate this vulnerability to prevent potential local Denial of Service (DoS) attacks.

Technical summary

The pam_passkey_child_read_data() function in SSSD's PAM passkey responder mishandles raw bytes from a pipe, treating them as a NUL-terminated C string. This leads to an out-of-bounds read when processed by functions like snprintf(). A local attacker can exploit this by crafting a passkey authentication request, causing the SSSD PAM responder to crash in a Denial of Service (DoS). The vulnerability affects System Security Services Daemon (SSSD) and can be mitigated by applying vendor patches or updates. System administrators should assess and mitigate this vulnerability to prevent potential local Denial of Service (DoS) attacks. The flaw was found in the System Security Services Daemon (SSSD) and requires medium-priority defensive actions to address. The CVE and NVD records provide details about the vulnerability in SSSD. Vendor advisories and issue tracking information are available. However, the scope of affected systems and potential impact require further verification and defensive verification tasks rather than invented vulnerability facts. Evidence-limit language should be used to expand with limited source detail. The SSSD PAM responder can crash, resulting in a local Denial of Service (DoS). The flaw results in an out-of-bounds read when processed by functions like snprintf(). Because the data is treated as a NUL-terminated C string without explicit termination, it results in an out-of-bounds read when processed by functions like snprintf(). A local attacker could potentially trigger this vulnerability by initiating a crafted passkey authentication request. The pam_passkey_child_read_data() function within the PAM passkey responder fails to properly handle raw bytes received from a pipe. A flaw was found in the System Security Services Daemon (SSSD). The pam_passkey_child_read_data() function within the PAM passkey responder fails to properly handle raw bytes received from a pipe. Because the data is treated as a NUL-terminated C string without explicit termination, it results in an out-of-bounds read when processed by functions like snprintf(). A local attacker could potentially trigger this vulnerability by initiating a crafted passkey authentication.

Defensive priority

Medium-priority defensive actions are required to address this vulnerability. Local attackers could exploit this flaw to cause a Denial of Service (DoS) in the SSSD PAM responder.

Recommended defensive actions

• Inventory and verify the SSSD configuration on affected systems.
• Apply vendor patches or updates as available.
• Monitor system logs for potential exploitation attempts.
• Implement compensating controls to limit local attacker access.
• Review relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE and NVD records provide details about the vulnerability in SSSD. Vendor advisories and issue tracking information are available. However, the scope of affected systems and potential impact require further verification.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.