Security readout for executives and security teams
Plain-English summary
Async applications using affected Apache HttpComponents Client versions may accept a valid TLS certificate issued for the wrong domain. An attacker positioned to intercept network traffic could impersonate a trusted server, exposing or altering sensitive data. The classic client is not affected.
Executive priority
Treat as an urgent remediation for internet-facing or sensitive async integrations. Establish exposure immediately and expedite upgrades where affected traffic carries secrets or business-critical data. Absence from KEV lowers evidence of current exploitation, but does not reduce the severe interception impact.
Technical view
CVE-2026-71290 is a CWE-295 hostname-verification failure. With the asynchronous transport, HostnameVerificationPolicy.BUILTIN does not enforce the expected hostname check. The CVSS 3.1 score is 9.1 because an unauthenticated network-positioned attacker could compromise confidentiality and integrity without user interaction; availability is not directly affected.
Likely exposure
Exposure requires Apache HttpComponents Client's asynchronous implementation with the affected BUILTIN policy. The source description says 5.4 or newer, while structured version data lists 5.4-alpha; confirm the precise affected range against Apache guidance. Classic HttpClient deployments are not affected.
Exploitation context
Exploitation requires an attacker able to intercept and modify client-server traffic and present a valid certificate for another domain. The supplied record is not in KEV and provides no evidence of active exploitation. Network-path access therefore limits opportunity, but successful attacks may be difficult for applications to detect.
Researcher notes
The failure is specific to the async transport; classic HttpClient is explicitly excluded. Review configuration and runtime construction, not dependency presence alone. The supplied sources contain an affected-version inconsistency, so avoid asserting a complete version range beyond the vendor's broad 5.4-or-newer statement and fixed version 5.6.4.
Mitigation direction
- Upgrade Apache HttpComponents Client to version 5.6.4 or later.
- Prioritize async clients carrying credentials, personal data, payment data, or privileged API traffic.
- Where upgrading is temporarily impossible, assess switching affected workloads to the unaffected classic client.
- Review Apache guidance for any additional supported mitigations or affected-version clarification.
Validation and detection
- Inventory the httpclient5 package version across applications, containers, and deployed dependency lockfiles.
- Identify applications using asynchronous HttpClient with HostnameVerificationPolicy.BUILTIN.
- Confirm deployed artifacts use version 5.6.4 or later after remediation.
- In a controlled test, verify certificates for mismatched hostnames are rejected.
- Confirm classic-only applications do not instantiate the asynchronous transport.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-295: Exact CWE lookup
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Open ATT&CK lookupCVE-2026-71290 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N3.95.2CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://lists.apache.org/thread/bhf7g2zwpom2ohvwjjjlonc93br2s8vqCVE reference, apache · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Certificate Validation
Improper Certificate Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.