How severe is CVE-2021-42753?

CVE-2021-42753 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2021-42753 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42753?

CVE-2021-42753 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42753?

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-2021-42753 published?

CVE-2021-42753 was published on 2022-02-02 and last updated on 2026-06-17.

CVE-2021-42753

CVE-2021-42753 is a high-severity vulnerability in Fortinet Fortiweb with a CVSS 3.x base score of 8.1. 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-22.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 8.5
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Fortinet Fortiweb
Published: 2022-02-02
Last modified: 2026-06-17

Description

An improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability [CWE-22] in FortiWeb management interface 6.4.1 and below, 6.3.15 and below, 6.2.x, 6.1.x, 6.0.x, 5.9.x and 5.8.x may allow an authenticated attacker to perform an arbitrary file and directory deletion in the device filesystem.

Frequently asked questions

What is CVE-2021-42753?: An improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability [CWE-22] in FortiWeb management interface 6.4.1 and below, 6.3.15 and below, 6.2.x, 6.1.x, 6.0.x, 5.9.x and 5.8.x may allow an authenticated attacker to perform an arbitrary file and directory deletion in the device filesystem.
How severe is CVE-2021-42753?: CVE-2021-42753 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2021-42753 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42753?: CVE-2021-42753 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42753?: 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-2021-42753 published?: CVE-2021-42753 was published on 2022-02-02 and last updated on 2026-06-17.

References

https://fortiguard.com/psirt/FG-IR-21-158

Affected products (1)

cpe:2.3:a:fortinet:fortiweb:*:*:*:*:*:*:*:*

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