SSSD NSS Responder OOB Read via GETHOSTBYADDR Causing DoS
CVE-2026-68742 Published on August 3, 2026
Sssd: sssd: nss responder out-of-bounds read via unchecked addrlen in gethostbyaddr
A flaw was found in SSSD. The sss_nss_protocol_parse_addr() function in the NSS responder does not validate the addrlen field against the remaining packet body size. A local attacker can exploit this via a crafted GETHOSTBYADDR request to the NSS responder socket, causing an out-of-bounds read and process crash, resulting in a denial of service.
Vulnerability Analysis
CVE-2026-68742 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Timeline
Reported to Red Hat.
Made public. 6 days later.
Weakness Type
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
Products Associated with CVE-2026-68742
stack.watch emails you whenever new vulnerabilities are published in Red Hat Enterprise Linux (RHEL) or Red Hat Openshift. Just hit a watch button to start following.
