CVE-2026-2967CWE-940

Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source

Medium · published February 23, 2026

CVSS v4.0
6.3
EPSS
1%
Percentile
55.6
In the wild
Unconfirmed
What it is

A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

The record
Technical detail
CVSS v4.0
6.3 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
EPSS
0.00786 · 55.6th percentile
Weakness
CWE-940 · Improper Verification of Source of a Communication Channel
Published
2026-02-23T02:32Z
EPSS history
Timeline
  • 23 FEB 02:32Z
    Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source
    cvelistv5