Summary
generated automatically from NVD dataThe SSL-VPN feature in Fortinet FortiOS validates only the first byte of the TLS MAC in finished messages, a weakness classed as CWE-20 (improper input validation). A remote attacker could exploit this by sending a crafted MAC field, making it easier to spoof encrypted content. The NVD description states the issue affects FortiOS before 4.3.13, and the CVSS v2.0 score is 5.0 (MEDIUM), with an integrity-only impact.
NVD description
The SSL-VPN feature in Fortinet FortiOS before 4.3.13 only checks the first byte of the TLS MAC in finished messages, which makes it easier for remote attackers to spoof encrypted content via a crafted MAC field.
EPSS · FIRST.org
2.1%probability of exploitation in the next 30 days
Higher than 81% of scored CVEs
EPSS (Exploit Prediction Scoring System) estimates, from observed exploitation activity, how likely a CVE is to be exploited in the next 30 days. It complements CVSS, which measures severity, not likelihood. Score of 2026-10-16, recomputed daily by FIRST.org.
CVSS v2.0 Score
Information
- Published
- 11 août 2015
- Updated
- 17 juin 2026
- Status
- Modified
- Source
- cve@mitre.org
Affected products
Weaknesses (CWE)
References (10)
- http://www.fortiguard.com/advisory/FG-IR-15-016/Vendor Advisory
- http://www.fortiguard.com/advisory/FG-IR-15-016/Vendor Advisory
Similar CVEs
Other vulnerabilities of type CWE-20
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