CVE-2026-5246 | Cesanta Mongoose up to 7.20 P-384 Public Key mongoose.c mg_tls_verify_cert_signature authorization

VDB-354827 · CVE-2026-5246 · GCVE-100-354827 CESANTA MONGOOSE UP TO 7.20 P-384 PUBLIC KEY MONGOOSE.C MG_TLS_VERIFY_CERT_SIGNATURE AUTHORIZATION HISTORYDIFFRELATEJSONXMLCTI Summaryinfo A vulnerability marked as critical has been reported in Cesanta Mongoose up to 7.20. Affected by this vulnerability is the function mg_tls_verify_cert_signature of the file mongoose.c of the component P-384 Public Key Handler. The manipulation leads to authorization. This vulnerability is uniquely identified as CVE-2026-5246. The attack is possible to be carried out remotely. Moreover, an exploit is present. It is suggested to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product. Detailsinfo A vulnerability, which was classified as critical, has been found in Cesanta Mongoose up to 7.20. This issue affects the function mg_tls_verify_cert_signature of the file mongoose.c of the component P-384 Public Key Handler. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is confidentiality, integrity, and availability. The identification of this vulnerability is CVE-2026-5246. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. It is declared as proof-of-concept. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product. Upgrading to version 7.21 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version. Productinfo Vendor Cesanta Name Mongoose Version 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 License open-source Website Product: https://github.com/cesanta/mongoose/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 5.6 VulDB Meta Temp Score: 5.1 VulDB Base Score: 5.6 VulDB Temp Score: 5.1 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Authorization CWE: CWE-639 / CWE-285 / CWE-266 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Access: Public Status: Proof-of-Concept Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Mongoose 7.21 Patch: 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1 Timelineinfo 04/02/2026 Advisory disclosed 04/02/2026 +0 days VulDB entry created 04/02/2026 +0 days VulDB entry last update Sourcesinfo Product: github.com Status: Confirmed CVE: CVE-2026-5246 (🔒) GCVE (CVE): GCVE-0-2026-5246 GCVE (VulDB): GCVE-100-354827 scip Labs: https://www.scip.ch/en/?labs.20161013 Entryinfo Created: 04/02/2026 09:48 Changes: 04/02/2026 09:48 (60) Complete: 🔍 Submitter: the_evilsocket Cache ID: 99:F6E:101 Submitinfo Accepted Submit #770104: Cesanta Mongoose 7.20 Authorization Bypass (by the_evilsocket) Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸