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.
References
| Link | Resource |
|---|---|
| https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71 | Patch |
| https://github.com/cesanta/mongoose/pull/3611 | Issue Tracking Patch |
| https://github.com/cesanta/mongoose/releases/tag/7.22 | Release Notes |
| https://github.com/cesanta/mongoose/security/advisories/GHSA-cc55-8v3r-59p8 | Exploit Vendor Advisory |
| https://github.com/cesanta/mongoose/security/advisories/GHSA-cc55-8v3r-59p8 | Exploit Vendor Advisory |
Configurations
History
18 Oct 2026, 20:10
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
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29 Sep 2026, 15:51
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Cesanta mongoose
Cesanta |
|
| CPE | cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:* | |
| References | () https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71 - Patch | |
| References | () https://github.com/cesanta/mongoose/pull/3611 - Issue Tracking, Patch | |
| References | () https://github.com/cesanta/mongoose/releases/tag/7.22 - Release Notes | |
| References | () https://github.com/cesanta/mongoose/security/advisories/GHSA-cc55-8v3r-59p8 - Exploit, Vendor Advisory |
Information
Published : 2026-08-20 18:16
Updated : 2026-10-18 20:10
NVD link : CVE-2026-73258
Mitre link : CVE-2026-73258
CVE.ORG link : CVE-2026-73258
JSON object : View
Products Affected
cesanta
- mongoose
CWE
CWE-697
Incorrect Comparison
