CVE-2026-64607
Medium
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.
SeverityMedium
CVSS5.3
Exploit probability—
Product
Apache Httpclient
PublishedJul 31, 2026
First seenJul 31, 2026
Weakness typeCWE-772CWE-772
How to fix
Update
- apache httpclient5.6.3 or later
- org.apache.httpcomponents.client5:httpclient55.6.3 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| apache httpclient | 5.0.0 ≤ v < 5.6.3 | 5.6.3 |
| org.apache.httpcomponents.client5:httpclient5Maven | 5.0-alpha1 ≤ v < 5.6.3 | 5.6.3 |
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