CVE-2026-73258: Mongoose is an embedded web server and network library. Prior to 7.22, a remote attacker can place a lone carriage return or line feed in multipart input…

PriorityP339medium6.5CVSS 3.1

AVNACLPRNUINSUCLILAN

EPSS

0.32%

25.6th percentile

Mongoose is an embedded web server and network library. Prior to 7.22, a remote attacker can place a lone carriage return or line feed in multipart input processed by mg_http_next_multipart() in src/http.c. The loops comparing s[b] and s[b + 1], and s[h2] and s[h2 + 1], use an incorrect AND condition and stop when either character resembles part of a CRLF terminator. This truncates headers, filenames, or boundaries and can cause an application to accept dangerous content after seeing a misleading Content-Type value. This issue is fixed in version 7.22.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
cesanta	mongoose	< 7.22	7.22

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