Low severity · published Feb 23, 2026
CVE-2026-2968
Cesanta Mongoose Poly1305 Authentication Tag tls_chacha20.c mg_chacha20_poly1305_decrypt signature verification
3.7
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 17% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
Mongoose · Cesanta
7.0; 7.1; 7.2; 7.3; 7.4; 7.5; +15 more · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-2968
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-2968
Exploit
https://github.com/dwBruijn/CVEs/blob/main/Mongoose/ChaCha20Poly1305.md
Exploit
https://github.com/dwBruijn/CVEs/blob/main/Mongoose/ChaCha20Poly1305.md#poc
Permissions Required
https://vuldb.com/?ctiid.347335
Third Party Advisory
https://vuldb.com/?id.347335
Third Party Advisory
https://vuldb.com/?submit.757091
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