CVE-2026-11404
published 2026-07-09CVE-2026-11404: Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled…
PriorityP347high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.61%
47.7th percentile
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_TLS_BUILTIN.
Affected
1 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cesanta | mongoose | < 7.22 | 7.22 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vendor_redhat7.5HIGH
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VulDB
Cesanta Mongoose up to 7.21 TLS Server mg_tls_server_recv_hello session_id_len out-of-bounds
vuldb·2026-07-29·CVSS 7.5
CVE-2026-11404 [HIGH] Cesanta Mongoose up to 7.21 TLS Server mg_tls_server_recv_hello session_id_len out-of-bounds
A vulnerability, which was classified as critical, has been found in Cesanta Mongoose up to 7.21. Impacted is the function mg_tls_server_recv_hello of the component TLS Server. Performing a manipulation of the argument session_id_len results in out-of-bounds read.
This vulnerability is reported as CVE-2026-11404. The attack is possible to be carried out remotely. No exploit exists.
It is advisable to upgrade the affected component.
GHSA
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello
ghsa_unreviewed·2026-07-09
CVE-2026-11404 [HIGH] CWE-125 Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_TLS_BUILTIN.
Red Hat
mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
vendor_redhat·2026-07-09·CVSS 7.5
CVE-2026-11404 [HIGH] CWE-125 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_TLS_BUILTIN.
A flaw was found in Mongoose. An out-of-bounds read vulnerability exists in the built-in TLS server function mg_tls_server_recv_hello(). A remote, unauthenticated attacker can exploit this by sending a specially crafted TLS ClientHello
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
bugzilla·2026-08-05·CVSS 7.5
CVE-2026-11404 [HIGH] CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on
Bugzilla
CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
bugzilla·2026-08-05·CVSS 7.5
CVE-2026-11404 [HIGH] CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on
Bugzilla
CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [epel-all]
bugzilla·2026-08-05·CVSS 7.5
CVE-2026-11404 [HIGH] CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [epel-all]
CVE-2026-11404 smplayer: Mongoose: Denial of Service via out-of-bounds read in TLS server [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG
Bugzilla
CVE-2026-11404 flmsg: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
bugzilla·2026-08-05·CVSS 7.5
CVE-2026-11404 [HIGH] CVE-2026-11404 flmsg: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
CVE-2026-11404 flmsg: Mongoose: Denial of Service via out-of-bounds read in TLS server [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_
Bugzilla
CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
bugzilla·2026-07-09·CVSS 7.5
CVE-2026-11404 [HIGH] CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
CVE-2026-11404 mongoose: Mongoose: Denial of Service via out-of-bounds read in TLS server
Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_TLS_BUILTIN.
2026-07-09
Published