Description
HttpClient based on the classic i/o model fails to correctly release the underlying connection back to the connection manager if it encounters an invalid or unsupported `Content-Encoding` header value in the response message. Please note this defect does not affect HttpClient based on the async i/o model. This issue affects Apache HttpComponents Client: from 5.0-alpha1 through 5.6.2.
Affected products
apache: httpclient
References2
- lists.apache.org/thread/qqfzo3fqcdk4l5496vz95ppvl4ty511q Mailing ListRelease Notes
- www.openwall.com/lists/oss-security/2026/08/13/5
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 41 · as of 13 November 2026
- CWE
- CWE-772
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