Information disclosure in Apache HttpClient

1) Configuration

EUVDB-ID: #VU109240

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-27820

CWE-ID: CWE-16 - Configuration

Exploit availability: No

Description

The issue may allow a remote attacker to bypass security restrictions.

The issue exists due to an error in PSL validation logic that disables domain checks, affecting cookie management and host name verification. A remote attacker can gain unauthorized access to sensitive information.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache Commons HttpClient: 5.4 - 5.4.2

CPE2.3

• cpe:2.3:a:apache_foundation:apache_commons_httpclient:5.4:*:*:*:*:*:*:*
• cpe:2.3:a:apache_foundation:apache_commons_httpclient:5.4.1:*:*:*:*:*:*:*
• cpe:2.3:a:apache_foundation:apache_commons_httpclient:5.4.2:*:*:*:*:*:*:*

External links

https://github.com/apache/httpcomponents-client/pull/574
https://github.com/apache/httpcomponents-client/pull/621
https://hc.apache.org/httpcomponents-client-5.4.x/index.html
https://lists.apache.org/thread/55xhs40ncqv97qvoocok44995xp5kqn8

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.