CVE-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 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.

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

Fixed

beb73a65a99619ff349c59037ea5197f27c7e533

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "7.22"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "DESCRIPTION",
        "REFERENCES"
    ]
}

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

7.3

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"