CVE-2026-64607CWE-772

CVE-2026-64607

Medium · published July 31, 2026

CVSS v3.1

5.3

EPSS

Percentile

39.2

In the wild

Unconfirmed

What it is

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.

The record

Technical detail

CVSS v3.1: 5.3 · MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0: Not supplied
EPSS: 0.00464 · 39.2th percentile
Weakness: CWE-772 · Missing Release of Resource after Effective Lifetime
Published: 2026-07-31T15:17Z

Affected products (1)

Product	Versions	Fixed in
apache/httpclient	≥ 5.0.0, < 5.6.3	5.6.3

References (2)

https://lists.apache.org/thread/qqfzo3fqcdk4l5496vz95ppvl4ty511q · [email protected]http://www.openwall.com/lists/oss-security/2026/08/13/5 · af854a3a-2127-422b-91ae-364da2661108

EPSS history

Timeline

31 JUL 10:12Z
Apache HttpComponents Client: Connection Leak on Content-Encoding Decode Error Leads to Pool Exhaustion DoS
cvelistv5