A flaw was found in SSSD. The sssnssprotocolfillinitgr() function in the NSS responder (src/responder/nss/nssprotocolgrent.c) pre-allocates the reply packet for all group entries using ssspacketgrow() but does not shrink the packet when groups are skipped (non-POSIX, incomplete, or filtered groups). ssspacketgrow() uses tallocreallocsize(), which does not zero-fill newly allocated memory. The trailing unwritten bytes therefore contain uninitialized heap data from the sssdnss process and are transmitted to the client at the grown packet length. A local attacker can exploit this by sending SSSNSSINITGR (0x0026) requests to the world-writable NSS responder socket (/var/lib/sss/pipes/nss), receiving uninitialized heap content in the reply tail. Through heap grooming (for example, a preceding getpwnam query), the leak can disclose other users' cached directory records and process heap pointers. The leaked data is limited to the sssdnss heap (directory-level information); credentials reside in separate sssdpam and sssdbe processes. Reported via PSIRTSUPT-20553 by BreachX Zero Day Labs.
A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted Online Certificate Status Protocol (OCSP) response during a TLS handshake. Due to a logic error in how gnutls processes multi-record OCSP responses, a client with OCSP verification enabled may incorrectly accept a revoked server certificate, potentially leading to a compromise of trust.
A flaw was found in the libxml2 library. This uncontrolled resource consumption vulnerability occurs when processing XML catalogs that contain repeated <nextCatalog> elements pointing to the same downstream catalog. A remote attacker can exploit this by supplying crafted catalogs, causing the parser to redundantly traverse catalog chains. This leads to excessive CPU consumption and degrades application availability, resulting in a denial-of-service condition.
A flaw was identified in the RelaxNG parser of libxml2 related to how external schema inclusions are handled. The parser does not enforce a limit on inclusion depth when resolving nested <include> directives. Specially crafted or overly complex schemas can cause excessive recursion during parsing. This may lead to stack exhaustion and application crashes, creating a denial-of-service risk.
A vulnerability was found in the netavark package, a network stack for containers used with Podman. Due to dns.podman search domain being removed, netavark may return external servers if a valid A/AAAA record is sent as a response. When creating a container with a given name, this name will be used as the hostname for the container itself, as the podman's search domain is not added anymore the container is using the host's resolv.conf, and the DNS resolver will try to look into the search domains contained on it. If one of the domains contain a name with the same hostname as the running container, the connection will forward to unexpected external servers.
A flaw was found in the interactive shell of the xmllint command-line tool, used for parsing XML files. When a user inputs an overly long command, the program does not check the input size properly, which can cause it to crash. This issue might allow attackers to run harmful code in rare configurations without modern protections.