How severe is CVE-2024-54021?

CVE-2024-54021 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2024-54021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-54021?

CVE-2024-54021 primarily affects Fortinet Fortiproxy. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-54021?

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

Does CVE-2024-54021 have an EU (EUVD) identifier?

Yes. CVE-2024-54021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-52244.

When was CVE-2024-54021 published?

CVE-2024-54021 was published on 2025-01-14 and last updated on 2026-06-17.

CVE-2024-54021

CVE-2024-54021 is a medium-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 6.5. 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-113.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-52244
Weakness: CWE-113
Affected product: Fortinet Fortiproxy
Published: 2025-01-14
Last modified: 2026-06-17

Description

An Improper Neutralization of CRLF Sequences in HTTP Headers ('http response splitting') vulnerability [CWE-113] in Fortinet FortiOS 7.2.0 through 7.6.0, FortiProxy 7.2.0 through 7.4.5 may allow a remote unauthenticated attacker to bypass the file filter via crafted HTTP headers.

Frequently asked questions

What is CVE-2024-54021?: An Improper Neutralization of CRLF Sequences in HTTP Headers ('http response splitting') vulnerability [CWE-113] in Fortinet FortiOS 7.2.0 through 7.6.0, FortiProxy 7.2.0 through 7.4.5 may allow a remote unauthenticated attacker to bypass the file filter via crafted HTTP headers.
How severe is CVE-2024-54021?: CVE-2024-54021 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2024-54021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-54021?: CVE-2024-54021 primarily affects Fortinet Fortiproxy. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-54021?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-54021 have an EU (EUVD) identifier?: Yes. CVE-2024-54021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-52244.
When was CVE-2024-54021 published?: CVE-2024-54021 was published on 2025-01-14 and last updated on 2026-06-17.

References

https://fortiguard.fortinet.com/psirt/FG-IR-24-282

Affected products (3)

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:7.6.0:*:*:*:*:*:*:*

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