CVE-2026-11404

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Source
https://cve.org/CVERecord?id=CVE-2026-11404
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-11404.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-11404
Published
2026-07-09T15:13:40.148Z
Modified
2026-07-15T01:49:07.155064125Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
Cesanta Mongoose before 7.22 Out-of-Bounds Read in MG_TLS_BUILTIN ClientHello Session ID Parsing
Details

Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mgtlsserverrecvhello(), which uses an attacker-controlled sessionidlen 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 MGTLSBUILTIN.

Database specific 
{
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
        "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/11xxx/CVE-2026-11404.json"
}
References

Affected packages

Git / github.com/cesanta/mongoose

Affected ranges

Type
GIT
Repo
https://github.com/cesanta/mongoose
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
beb73a65a99619ff349c59037ea5197f27c7e533
Fixed
c288ac1f38424ffdd4d2fd5e1893fd4962642db3
Database specific 
{
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "7.22"
        }
    ]
}

Affected versions

3.*
3.2
3.3
3.4
3.5
3.6
3.7
3.8
4.*
4.0
4.1
5.*
5.0
5.1
5.2
5.3
5.4
5.5
5.5_20140120
5.6
6.*
6.0
6.1
6.10
6.11
6.12
6.13
6.14
6.15
6.16
6.17
6.18
6.2
6.3
6.4
6.5
6.6
6.7
6.9
7.*
7.0
7.1
7.11
7.12
7.13
7.14
7.15
7.16
7.17
7.18
7.19
7.2
7.20
7.21
7.22
7.3
7.4
7.5
7.6
7.7
7.8

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-11404.json"