How severe is CVE-2025-66373?

CVE-2025-66373 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-66373 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66373?

CVE-2025-66373 affects Akamai Akamaighost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66373?

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

Does CVE-2025-66373 have an EU (EUVD) identifier?

Yes. CVE-2025-66373 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201241.

When was CVE-2025-66373 published?

CVE-2025-66373 was published on 2025-12-04 and last updated on 2026-06-17.

CVE-2025-66373

CVE-2025-66373 is a medium-severity vulnerability in Akamai Akamaighost with a CVSS 3.x base score of 4.8. 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-444.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-201241
Weakness: CWE-444
Affected product: Akamai Akamaighost
Published: 2025-12-04
Last modified: 2026-06-17

Description

Akamai Ghost on Akamai CDN edge servers before 2025-11-17 has a chunked request body processing error that can result in HTTP request smuggling. When Akamai Ghost receives an invalid chunked body that includes a chunk size different from the actual size of the following chunk data, under certain circumstances, Akamai Ghost erroneously forwards the invalid request and subsequent superfluous bytes to the origin server. An attacker could hide a smuggled request in these superfluous bytes. Whether this is exploitable depends on the origin server's behavior and how it processes the invalid request it receives from Akamai Ghost.

Frequently asked questions

What is CVE-2025-66373?: Akamai Ghost on Akamai CDN edge servers before 2025-11-17 has a chunked request body processing error that can result in HTTP request smuggling. When Akamai Ghost receives an invalid chunked body that includes a chunk size different from the actual size of the following chunk data, under certain circumstances, Akamai Ghost erroneously forwards the invalid request and subsequent superfluous bytes to the origin server. An attacker could hide a smuggled request in these superfluous bytes. Whether this is exploitable depends on the origin server's behavior and how it processes the invalid request it receives from Akamai Ghost.
How severe is CVE-2025-66373?: CVE-2025-66373 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-66373 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66373?: CVE-2025-66373 affects Akamai Akamaighost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66373?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-66373 have an EU (EUVD) identifier?: Yes. CVE-2025-66373 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201241.
When was CVE-2025-66373 published?: CVE-2025-66373 was published on 2025-12-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:akamai:akamaighost:*:*:*:*:*:*:*:*

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