CVEvulnerability

CVE-2026-73256

9.1 CRITICAL Published 2026-08-20 Modified 2026-10-18 Official page ↗
Status
Analyzed
Published
2026-08-20
Last modified
2026-10-18
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.1 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-444

Description

Mongoose is an embedded web server and network library. Prior to 7.22, a remote unauthenticated attacker can exploit an HTTP/1.0 reverse-proxy deployment by sending a request with Transfer-Encoding: chunked and conflicting framing. The http_cb() function in src/http.c tests hm.proto.len with an impossible greater-than-eight condition even though mg_http_parse() requires an eight-byte protocol string, so is_http_1_0 is never set. Mongoose consequently processes chunked encoding that an HTTP/1.0 proxy can ignore, enabling request smuggling and unauthorized access or state changes. This issue is fixed in version 7.22.

Affected configurations

• cesanta mongoose (< 7.22)

Related

Weakness · CWE (1)

  • CWE-444 Inconsistent Interpretation of HTTP Requests weakness

References