How severe is CVE-2025-27820?

CVE-2025-27820 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2025-27820 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27820?

CVE-2025-27820 primarily affects Apache Httpclient. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-27820?

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-2025-27820 have an EU (EUVD) identifier?

Yes. CVE-2025-27820 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12102.

When was CVE-2025-27820 published?

CVE-2025-27820 was published on 2025-04-24 and last updated on 2026-06-17.

CVE-2025-27820

CVE-2025-27820 is a high-severity vulnerability in Apache Httpclient with a CVSS 3.x base score of 7.5. 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-12102
Weakness: CWE-295
Affected product: Apache Httpclient
Published: 2025-04-24
Last modified: 2026-06-17

Description

A bug in PSL validation logic in Apache HttpClient 5.4.x disables domain checks, affecting cookie management and host name verification. Discovered by the Apache HttpClient team. Fixed in the 5.4.3 release

Frequently asked questions

What is CVE-2025-27820?: A bug in PSL validation logic in Apache HttpClient 5.4.x disables domain checks, affecting cookie management and host name verification. Discovered by the Apache HttpClient team. Fixed in the 5.4.3 release
How severe is CVE-2025-27820?: CVE-2025-27820 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2025-27820 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27820?: CVE-2025-27820 primarily affects Apache Httpclient. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-27820?: 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-2025-27820 have an EU (EUVD) identifier?: Yes. CVE-2025-27820 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12102.
When was CVE-2025-27820 published?: CVE-2025-27820 was published on 2025-04-24 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:apache:httpclient:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_tools:10:*:*:*:*:vmware_vsphere:*:*

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