High severity · published Apr 2, 2026
CVE-2026-5246
Cesanta Mongoose P-384 Public Key mongoose.c mg_tls_verify_cert_signature authorization
8.1
CVSS
0.6%
EPSS
No
On KEV
Description
A vulnerability was determined in Cesanta Mongoose up to 7.20. Affected is the function mg_tls_verify_cert_signature of the file mongoose.c of the component P-384 Public Key Handler. Executing a manipulation can lead to authorization bypass. The attack can be executed remotely. Attacks of this nature are highly complex. The exploitability is told to be difficult. The exploit has been publicly disclosed and may be utilized. Upgrading to version 7.21 is able to address this issue. This patch is called 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. The affected component should be upgraded. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% 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-2026-5246
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-5246
Product
https://github.com/cesanta/mongoose/
Patch
https://github.com/cesanta/mongoose/commit/0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1
Product
https://github.com/cesanta/mongoose/releases/tag/7.21
Third Party Advisory
https://vuldb.com/submit/770104
Third Party Advisory
https://vuldb.com/vuln/354827
Permissions Required
https://vuldb.com/vuln/354827/cti
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