CVE-2013-4635: Integer overflow in the SdnToJewish function in jewish.c in the Calendar component in PHP before 5.3.26 and...

Security readout for executives and security teams

This is a denial-of-service flaw in older PHP calendar handling. A very large value passed to PHP's jdtojewish function can trigger an integer overflow and hang the application. The likely business impact is service disruption on legacy PHP 5.3 or 5.4 systems that expose this function to user-controlled input. Exposure is most plausible in legacy PHP applications running affected 5.3 or 5.4 releases with the Calendar extension enabled and code paths where users can influence values passed to jdtojewish. The provided structured affected-product data is incomplete, so confirm with installed PHP versions and vendor packages. Prioritize remediation if any internet-facing or business-critical service still runs affected PHP 5.3 or 5.4 code using Calendar functions. Otherwise, handle through legacy platform upgrade planning, because the main confirmed impact is denial of service and the exploitation evidence is limited. Mitigation focus: Upgrade PHP to 5.3.26, 5.4.16, or a later vendor-fixed release.; Prefer migration from obsolete PHP 5.x to a currently supported PHP release.; Apply Ubuntu or SUSE package updates where those distributions manage PHP..

Prepared

Jun 14, 2026, 22:07 UTC (UTC+00:00)

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