CVE-2026-2968 Details
Description
A vulnerability was detected in Cesanta Mongoose up to 7.20. This impacts the function mg_chacha20_poly1305_decrypt of the file /src/tls_chacha20.c of the component Poly1305 Authentication Tag Handler. The manipulation results in improper verification of cryptographic signature. The attack may be launched remotely. This attack is characterized by high complexity. The exploitability is said to be difficult. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
A vulnerability exists in Cesanta Mongoose versions up to 7.20 within the ChaCha20-Poly1305 decryption function. This vulnerability arises because the function fails to verify the Poly1305 authentication tag during decryption, allowing for improper verification of cryptographic signatures. As a result, an attacker could remotely exploit this flaw, modifying encrypted data in transit with byte-level precision. This issue renders TLS connections using Mongoose's built-in TLS implementation completely unauthenticated.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Feb 23, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/dwBruijn/CVEs/blob/main/Mongoose/ChaCha20Poly1305.md | [email protected] | ExploitThird Party Advisory |
| https://github.com/dwBruijn/CVEs/blob/main/Mongoose/ChaCha20Poly1305.md#poc | [email protected] | ExploitThird Party Advisory |
| https://vuldb.com/?ctiid.347335 | [email protected] | Permissions RequiredVDB Entry |
| https://vuldb.com/?id.347335 | [email protected] | Third Party AdvisoryVDB Entry |
| https://vuldb.com/?submit.757091 | [email protected] | Third Party AdvisoryVDB Entry |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-345 | Insufficient Verification of Data Authenticity | [email protected] |
| CWE-347 | Improper Verification of Cryptographic Signature | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| cesanta mongoose | <= 7.20 |
CPE
Remediation
| |
Change History
5 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 29, 2026 | Data Remediation | [email protected] |
| Feb 23, 2026 | Initial Analysis | [email protected] |
| Feb 23, 2026 | New CVE Received | [email protected] |