Paper/Archive/CVE-2026-71290

CVE-2026-71290

Apache Software Foundation Apache HttpComponents Client — Apache HttpComponents Client: TLS hostname verification silently disabled on the async transport (default config, MITM)

EPSS 0.3%CVSS 9.1

critical.is priorityof 100

CVSS 9.1 (ADP)9.1 / 10 × 3027.3 Not in CISA KEV+300.0 EPSS percentile 26.3.263 × 205.3 No public exploit+100.0 SSVC exploitation: none+100.0

Description · from the CVE record

Improper TLS hostname verification vulnerability in Apache HttpComponents Client 5.4 or newer. HostnameVerificationPolicy#BUILTIN setting has no effect when used with the async version of HttpClient. An attacker that can intercept and modify traffic between the client and the server can impersonate the server by presenting a valid certificate for a different domain. Please note the classic version of HttpClient is not affected by this vulnerability. Affected users are recommended to upgrade to at least version 5.6.4, which fixes the issue.

Affected

ProductAffectedFixed inSource

Apache HttpComponents Client5.4-alpha – 5.6.3–CNA

Scores by source

CISA ADP9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

advisorylists.apache.org/thread/bhf7g2zwpom2ohvwjjjlonc93br2s8vq refopenwall.com/lists/oss-security/2026/08/13/6