How severe is CVE-2021-26105?

CVE-2021-26105 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2021-26105 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26105?

CVE-2021-26105 primarily affects Fortinet Fortisandbox. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26105?

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

Does CVE-2021-26105 have an EU (EUVD) identifier?

Yes. CVE-2021-26105 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12926.

When was CVE-2021-26105 published?

CVE-2021-26105 was published on 2025-03-24 and last updated on 2026-06-17.

CVE-2021-26105

CVE-2021-26105 is a medium-severity vulnerability in Fortinet Fortisandbox with a CVSS 3.x base score of 6.8. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-12926
Weakness: CWE-787
Affected product: Fortinet Fortisandbox
Published: 2025-03-24
Last modified: 2026-06-17

Description

A stack-based buffer overflow vulnerability (CWE-121) in the profile parser of FortiSandbox version 3.2.2 and below, version 3.1.4 and below may allow an authenticated attacker to potentially execute unauthorized code or commands via specifically crafted HTTP requests.

Frequently asked questions

What is CVE-2021-26105?: A stack-based buffer overflow vulnerability (CWE-121) in the profile parser of FortiSandbox version 3.2.2 and below, version 3.1.4 and below may allow an authenticated attacker to potentially execute unauthorized code or commands via specifically crafted HTTP requests.
How severe is CVE-2021-26105?: CVE-2021-26105 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2021-26105 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26105?: CVE-2021-26105 primarily affects Fortinet Fortisandbox. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26105?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-26105 have an EU (EUVD) identifier?: Yes. CVE-2021-26105 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12926.
When was CVE-2021-26105 published?: CVE-2021-26105 was published on 2025-03-24 and last updated on 2026-06-17.

References

https://fortiguard.fortinet.com/psirt/FG-IR-20-234

Affected products (2)

cpe:2.3:a:fortinet:fortisandbox:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.0.0:*:*:*:*:*:*:*

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