CVE-2026-73251 Details
Mongoose is an embedded web server and network library. Prior to 7.23, a network attacker can impersonate a TLS server to a Mongoose client configured with a multi-certificate CA bundle. In src/tls_builtin.c, the mg_tls_init() function stores the bundle in tls->ca_bundle_der while tls->ca_der.len remains zero, and mg_tls_recv_cert() uses tls_bundle_find() to accept a Common Name match without calling mg_tls_verify_cert_signature(). A forged self-signed certificate can therefore satisfy hostname and CertificateVerify checks and enable interception, credential disclosure, traffic modification, and malicious responses. This issue is fixed in version 7.23.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-73251
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.19 Probability of exploitation activity being observed over the next 30 days (8th percentile)
CVSS score for CVE-2026-73251
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
9.1 Critical
Products affected by CVE-2026-73251
Mongoose 6.15
Mongoose 6.16
Mongoose 6.17
Mongoose 6.18
Mongoose 6.4
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
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CVE-2026-73251 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
CN 99 21.62%
US 56 12.23%
BR 55 12.01%
DE 48 10.48%
KR 44 9.61%
VN 18 3.93%
TR 13 2.84%
MY 12 2.62%
PL 10 2.18%
IT 9 1.97%

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CVE-2026-73251 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 219 66.97%
Technology 102 31.19%
Government/Politics 2 0.61%
Utilities 1 0.31%
Media/Entertainment 1 0.31%
Energy/Resources 1 0.31%
Retail 1 0.31%

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