How severe is CVE-2020-29016?

CVE-2020-29016 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-29016 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-29016?

CVE-2020-29016 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-29016?

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

When was CVE-2020-29016 published?

CVE-2020-29016 was published on 2021-01-14 and last updated on 2026-06-17.

CVE-2020-29016

CVE-2020-29016 is a critical-severity vulnerability in Fortinet Fortiweb with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Fortinet Fortiweb
Published: 2021-01-14
Last modified: 2026-06-17

Description

A stack-based buffer overflow vulnerability in FortiWeb 6.3.0 through 6.3.5 and version before 6.2.4 may allow an unauthenticated, remote attacker to overwrite the content of the stack and potentially execute arbitrary code by sending a crafted request with a large certname.

Frequently asked questions

What is CVE-2020-29016?: A stack-based buffer overflow vulnerability in FortiWeb 6.3.0 through 6.3.5 and version before 6.2.4 may allow an unauthenticated, remote attacker to overwrite the content of the stack and potentially execute arbitrary code by sending a crafted request with a large certname.
How severe is CVE-2020-29016?: CVE-2020-29016 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-29016 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-29016?: CVE-2020-29016 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-29016?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-29016 published?: CVE-2020-29016 was published on 2021-01-14 and last updated on 2026-06-17.

References

https://www.fortiguard.com/psirt/FG-IR-20-125

Affected products (1)

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

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