The Red Hat security advisory RHSA-2026:16866 addresses eight vulnerabilities in FreeRDP affecting Red Hat Enterprise Linux 9.4 Extended Update Support and related builds. The vulnerabilities include denial of service via use-after-free (CVE-2026-25952), double free during disconnect (CVE-2026-26986), endless blocking loop in Stream_EnsureCapacity (CVE-2026-27951), heap-buffer-overflow in bitmap_cache_put (CVE-2026-29775), out-of-bounds read in ADPCM decoders due to missing bounds checks (CVE-2026-31885), division-by-zero in ADPCM decoders when nBlockAlign is zero (CVE-2026-31884), denial of service via crafted audio data (CVE-2026-31883), and information disclosure via heap memory out-of-bounds read (CVE-2026-33985). These vulnerabilities impact the freerdp client used to connect to RDP servers and can cause crashes, memory corruption, or data leaks. The advisory provides updated freerdp packages to remediate these issues.

The vulnerabilities collectively can lead to denial of service conditions through crashes caused by use-after-free, double free, infinite loops, and crafted audio data. Memory corruption vulnerabilities such as heap-buffer-overflow and out-of-bounds reads may allow information disclosure or destabilize the client. The division-by-zero error can also cause crashes. These issues affect the stability and confidentiality of the FreeRDP client when connecting to RDP servers.

Red Hat has released updated freerdp packages as part of Red Hat Enterprise Linux 9.4 Extended Update Support to address these vulnerabilities. Users should apply the security update RHSA-2026:16866 promptly to remediate these issues. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are specified beyond applying the official patches.