Description
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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Cesanta | Mongoose | 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 7.10, 7.11, 7.12, 7.13, 7.14, 7.15, 7.16, 7.17, 7.18, 7.19, 7.20 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | swupdate | 2025.12+dfsg-10 | — |
| Debian 13 | swupdate | No fix yet | — |
| Debian 12 | swupdate | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | opencpn | No fix yet | — |
| Ubuntu 26.04 LTS | opencpn | No fix yet | — |
| Ubuntu 25.10 | opencpn | No fix yet | — |
| Ubuntu 24.04 LTS | opencpn | No fix yet | — |
| Ubuntu 22.04 LTS | opencpn | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | opencpn | No fix yet | — |
References
- VDB-347334 | Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source vdb-entry technical-description
- VDB-347334 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #755450 | Cesanta Mongoose Embedded Web Server 7.20 Improper Validation of Specified Index, Position, or Offset in I third-party-advisory
- https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md related
- https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md#poc exploit