Threats Tagged 'cve-2026-59679'

fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) indexes the per-character encoding[] array using num_chars from the FS_QueryXBitmaps16 reply, but that array was allocated with a size derived from num_extents in the separate FS_QueryXExtents16 reply. The two CARD32 fields are never cross-checked. A malicious or compromised font server can send a small num_extents (e.g. 1) in the extents reply, then a large num_chars (e.g. 100000) in the bitmaps reply. This causes attacker-controlled out-of-bounds heap read and writes.

Two security vulnerabilities have been identified in the X.Org X11 libXfont2 runtime library affecting Red Hat Enterprise Linux 9 and related variants. These include an out-of-bounds read/write in the Font Server Client encoding (CVE-2026-59679) and a privilege escalation via a heap buffer overflow in the Font Server Client (CVE-2026-44950). Red Hat has released security updates addressing these issues. The vulnerabilities are rated as having an important security impact by Red Hat Product Security.

Two security vulnerabilities have been identified in the X.Org X11 libXfont2 runtime library affecting Red Hat Enterprise Linux 10 and related products. These include an out-of-bounds read/write issue (CVE-2026-59679) and a privilege escalation via heap buffer overflow (CVE-2026-44950) in the Font Server Client component. Red Hat has released security updates addressing these issues. The vulnerabilities are rated with high severity by the source data. The update is available for multiple architectures including x86_64, s390x, ppc64le, and aarch64. Users should apply the official Red Hat patches to remediate these vulnerabilities.

Two security vulnerabilities have been identified in the X.Org X11 libXfont2 runtime library affecting Red Hat Enterprise Linux 8. These include an out-of-bounds read/write in the Font Server Client encoding and a privilege escalation via a heap buffer overflow in the Font Server Client. Red Hat has issued a security advisory with updates to address these issues. The vulnerabilities are rated with an important security impact by Red Hat Product Security. Updated packages are available for multiple architectures and variants of Red Hat Enterprise Linux 8.