Skip to content
OpenAdvisories
Medium · 6.5 CVE-2026-73255 EUVD-2026-63499

Mongoose: Path traversal in SSI #include directives enables arbitrary file read

Published Aug 20, 2026 · Updated Aug 25, 2026 · Assigned by GitHub_M

Description

Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can control an SSI-enabled file can place directory traversal sequences in an #include file or #include virtual directive. The mg_ssi() function in src/ssi.c concatenates the directive argument into a filesystem path without calling mg_path_is_sane(), allowing an MG_ENABLE_SSI deployment with ssi_pattern configured to disclose files readable by the Mongoose process. This issue is fixed in version 7.22.

Affected products

VendorProductAffectedFixed
cesanta mongoose < 7.22 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 mongoose 7.22+ds-1 —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 mongoose No fix yet —

References