How severe is CVE-2019-15703?

CVE-2019-15703 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2019-15703 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15703?

CVE-2019-15703 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-15703?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-15703 published?

CVE-2019-15703 was published on 2019-10-24 and last updated on 2026-06-17.

CVE-2019-15703

CVE-2019-15703 is a high-severity vulnerability in Fortinet Fortios with a CVSS 3.x base score of 7.5. 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-331.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 2.6
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-331
Affected product: Fortinet Fortios
Published: 2019-10-24
Last modified: 2026-06-17

Description

An Insufficient Entropy in PRNG vulnerability in Fortinet FortiOS 6.2.1, 6.2.0, 6.0.8 and below for device not enable hardware TRNG token and models not support builtin TRNG seed allows attacker to theoretically recover the long term ECDSA secret in a TLS client with a RSA handshake and mutual ECDSA authentication via the help of flush+reload side channel attacks in FortiGate VM models only.

Frequently asked questions

What is CVE-2019-15703?: An Insufficient Entropy in PRNG vulnerability in Fortinet FortiOS 6.2.1, 6.2.0, 6.0.8 and below for device not enable hardware TRNG token and models not support builtin TRNG seed allows attacker to theoretically recover the long term ECDSA secret in a TLS client with a RSA handshake and mutual ECDSA authentication via the help of flush+reload side channel attacks in FortiGate VM models only.
How severe is CVE-2019-15703?: CVE-2019-15703 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2019-15703 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15703?: CVE-2019-15703 affects Fortinet Fortios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-15703?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-15703 published?: CVE-2019-15703 was published on 2019-10-24 and last updated on 2026-06-17.

References

https://fortiguard.com/psirt/FG-IR-19-186

Affected products (1)

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

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