CVE-2013-7439: Multiple off-by-one errors in the (1) MakeBigReq and (2) SetReqLen macros in include/X11/Xlibint.h in X11R6...

Security readout for executives and security teams

CVE-2013-7439 is a buffer overflow flaw in X11/libX11 request-length handling. A crafted request could trigger memory corruption with unspecified impact. The provided sources identify X11R6.x and libX11 before 1.6.0; no CVSS score or active exploitation evidence is provided. Exposure is most likely on systems or products that still ship or link against X11R6.x or libX11 earlier than 1.6.0. Distribution advisories from Ubuntu and Debian indicate packaged operating system exposure existed. Current risk depends on whether vulnerable libX11 remains installed or bundled. Treat this as a legacy dependency cleanup and patch-verification item, not an emergency based on the supplied evidence. The impact is unspecified and active exploitation is not shown, but vulnerable X11 libraries can persist in old systems and bundled applications. Mitigation focus: Inventory systems and bundled applications for libX11 versions before 1.6.0.; Apply vendor security updates from the relevant operating system or product supplier.; Prioritize Ubuntu, Debian, Oracle, and legacy Unix/Linux assets using X11 libraries..

Prepared

Jun 13, 2026, 22:56 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.