How severe is CVE-2015-5965?

CVE-2015-5965 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2015-5965 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-5965?

CVE-2015-5965 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2015-5965?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2015-5965 published?

CVE-2015-5965 was published on 2015-08-11 and last updated on 2026-06-17.

CVE-2015-5965

CVE-2015-5965 is a medium-severity vulnerability in Fortinet Fortios with a CVSS 2.0 base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Fortinet Fortios
Published: 2015-08-11
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2015-5965?: 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.
How severe is CVE-2015-5965?: CVE-2015-5965 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2015-5965 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-5965?: CVE-2015-5965 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2015-5965?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-5965 published?: CVE-2015-5965 was published on 2015-08-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

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