CVE-2026-73256
mongoose: Mongoose: HTTP/1.0 detection off-by-one enables request smuggling via chunked TE
Severity by source
Trivy's own label is CRITICAL. Rated critical by Red Hat, Julia.
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 packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| julia::Julia Ecosystem Security Advisories | Mongoose_jll | no fix listed |
| debian 14 | mongoose | 7.22+ds-1 |
| rapidfort fedora 43 | mongoose, mongoose-devel, mongoose-lib | 3.1-30.fc43 |
Show all 5 entries from 3 sources
| Source | Package | Fixed in |
|---|---|---|
| julia::Julia Ecosystem Security Advisories | Mongoose_jll | no fix listed |
| debian 14 | mongoose | 7.22+ds-1 |
| rapidfort fedora 43 | mongoose | 3.1-30.fc43 |
| rapidfort fedora 43 | mongoose-devel | 3.1-30.fc43 |
| rapidfort fedora 43 | mongoose-lib | 3.1-30.fc43 |
References
- https://access.redhat.com/security/cve/CVE-2026-73256
- https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71
- https://github.com/cesanta/mongoose/pull/3611
- https://github.com/cesanta/mongoose/releases/tag/7.22
- https://github.com/cesanta/mongoose/security/advisories/GHSA-mgp5-rjrv-h5j3
- https://nvd.nist.gov/vuln/detail/CVE-2026-73256
- https://www.cve.org/CVERecord?id=CVE-2026-73256