CVE-2026-128021 · Runtime
NO FIX YET · SEE WHAT TO DO
FrankenPHP before 1.13.2 never clears libxml error state between requests in worker mode, so a later client can read earlier clients' libxml errors. An attacker can get other clients' parsed-document fragments and server filesystem paths.
first public Oct 21, 2026 · 1 source
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Only servers running FrankenPHP in worker mode are exposed, because worker threads persist state across requests. Servers that run FrankenPHP in the default mode, or that do not use libxml, are less exposed. unknown whether the sources list any further configuration conditions.
Not affected if default-config, non-worker-mode
Who cares frankenphp, libxml, php, worker-mode
frankenphp version shows the installed version; below 1.13.2 is affected1.13.2 or laterFrankenPHP before 1.13.2 contains an information disclosure vulnerability that allows later clients to read earlier clients' libxml errors because worker mode never resets LIBXML(error_list) between requests. Attackers sending requests to the same worker thread can call libxml_get_errors() or libxml_get_last_error() to obtain other clients' parsed-document fragments and server filesystem paths.
This page as .md · .json · CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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