How severe is CVE-2019-17656?

CVE-2019-17656 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2019-17656 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-17656?

CVE-2019-17656 primarily affects Fortinet Fortiproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-17656?

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

When was CVE-2019-17656 published?

CVE-2019-17656 was published on 2021-04-12 and last updated on 2026-06-17.

CVE-2019-17656

CVE-2019-17656 is a medium-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 5.4. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 4.0
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Fortinet Fortiproxy
Published: 2021-04-12
Last modified: 2026-06-17

Description

A Stack-based Buffer Overflow vulnerability in the HTTPD daemon of FortiOS 6.0.10 and below, 6.2.2 and below and FortiProxy 1.0.x, 1.1.x, 1.2.9 and below, 2.0.0 and below may allow an authenticated remote attacker to crash the service by sending a malformed PUT request to the server. Fortinet is not aware of any successful exploitation of this vulnerability that would lead to code execution.

Frequently asked questions

What is CVE-2019-17656?: A Stack-based Buffer Overflow vulnerability in the HTTPD daemon of FortiOS 6.0.10 and below, 6.2.2 and below and FortiProxy 1.0.x, 1.1.x, 1.2.9 and below, 2.0.0 and below may allow an authenticated remote attacker to crash the service by sending a malformed PUT request to the server. Fortinet is not aware of any successful exploitation of this vulnerability that would lead to code execution.
How severe is CVE-2019-17656?: CVE-2019-17656 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2019-17656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-17656?: CVE-2019-17656 primarily affects Fortinet Fortiproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-17656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-17656 published?: CVE-2019-17656 was published on 2021-04-12 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*

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