How severe is CVE-2021-26115?

CVE-2021-26115 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26115 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26115?

CVE-2021-26115 affects Fortinet Fortiwan. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26115?

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.

Does CVE-2021-26115 have an EU (EUVD) identifier?

Yes. CVE-2021-26115 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12936.

When was CVE-2021-26115 published?

CVE-2021-26115 was published on 2024-12-19 and last updated on 2026-06-17.

CVE-2021-26115

CVE-2021-26115 is a high-severity vulnerability in Fortinet Fortiwan with a CVSS 3.x base score of 7.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-12936
Weakness: CWE-78
Affected product: Fortinet Fortiwan
Published: 2024-12-19
Last modified: 2026-06-17

Description

An OS command injection (CWE-78) vulnerability in FortiWAN version 4.5.7 and below Command Line Interface may allow a local, authenticated and unprivileged attacker to escalate their privileges to root via executing a specially-crafted command.An OS command injection (CWE-78) vulnerability in FortiWAN Command Line Interface may allow a local, authenticated and unprivileged attacker to escalate their privileges to root via executing a specially-crafted command.

Frequently asked questions

What is CVE-2021-26115?: An OS command injection (CWE-78) vulnerability in FortiWAN version 4.5.7 and below Command Line Interface may allow a local, authenticated and unprivileged attacker to escalate their privileges to root via executing a specially-crafted command.An OS command injection (CWE-78) vulnerability in FortiWAN Command Line Interface may allow a local, authenticated and unprivileged attacker to escalate their privileges to root via executing a specially-crafted command.
How severe is CVE-2021-26115?: CVE-2021-26115 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26115 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26115?: CVE-2021-26115 affects Fortinet Fortiwan. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26115?: 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.
Does CVE-2021-26115 have an EU (EUVD) identifier?: Yes. CVE-2021-26115 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12936.
When was CVE-2021-26115 published?: CVE-2021-26115 was published on 2024-12-19 and last updated on 2026-06-17.

References

https://fortiguard.fortinet.com/psirt/FG-IR-21-069

Affected products (1)

cpe:2.3:a:fortinet:fortiwan:*:*:*:*:*:*:*:*

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