CVE-2026-6986
Description
A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This issue affects the function mg_aes_gcm_decrypt of the file /src/tls_aes128.c of the component GCM Authentication Tag Handler. Such manipulation leads to improper verification of cryptographic signature. The attack may be performed from remote. A high complexity level is associated with this attack. The exploitability is assessed as difficult. The exploit has been disclosed publicly and may be used. Upgrading to version 7.21 is capable of addressing this issue. It is advisable to upgrade the affected component. VulDB has contacted the vendor early and they confirmed quickly, that this issue got fixed already.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-6986
Vendor advisory: cna@vuldb.com — https://github.com/cesanta/mongoose/releases/tag/7.21
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | forky | fixed | 0 |
| debian | sid | fixed | 0 |
| debian | bookworm | affected | |
| debian | bullseye | affected | |
| debian | trixie | affected | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| cesanta | mongoose | {"startIncluding":"7.0","endExcluding":"7.21"} | 7.21 |
References
CWEs
CWE-345 CWE-347
Verify integrity in audit chain (admin only). AS-IS.