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TI-2026-58468 Aliases CVE-2026-85124

@fastify/http-proxy vulnerable to prefix escape via backslash dot-segments

Priority MEDIUM 40CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 4 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-22 and the CVSS impact.

Summary

@fastify/http-proxy versions before 11.6.2 do not validate proxied HTTP request paths for backslash based dot-segments before forwarding them to the configured upstream. The plain HTTP request handler skips the destination validation that the WebSocket path performs, and the underlying reply-from library only rejects forward-slash traversal, so a request containing backslash dot-segments can escape the boundary set by the prefix and rewritePrefix options. An unauthenticated network attacker can use this to reach upstream paths that were meant to stay hidden behind the proxy, resulting in disclosure of internal endpoints. This is a path traversal issue (CWE-22). Users should upgrade to @fastify/http-proxy 11.6.2 or later.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00737 54th percentileScored 2026-11-07
Fix Partial @fastify/http-proxy (@fastify/http-proxy): 11.6.2Red Hat: 4 advisoriesRed Hat: 4 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
fastify@fastify/http-proxybefore 11.6.211.6.2Patch availableCNA
  • @fastify/http-proxy Vendorfastify Affected before 11.6.2 Fixed in 11.6.2 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fastify:fastify\/http-proxy:*:*:*:*:*:node.js:*:*before 11.6.2Vulnerablefastify
  • cpe:2.3:a:fastify:fastify\/http-proxy:*:*:*:*:*:node.js:*:* Versions before 11.6.2 Vulnerable ·fastify

Remediation

  • Fix · CNA @fastify/http-proxy (@fastify/http-proxy) Fixed in 11.6.2

Red Hat 4 advisories

  • RHSA-2026:90321 Released 2026-10-26 · Red Hat rating Critical
    Red Hat OpenShift Dev Spaces 3.31.0 Release.
    • Red Hat OpenShift Dev Spaces 3.31 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/jetbrains-ide-rhel9 +8
  • RHSA-2026:87410 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 2.25.12 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-codeflare-operator-rhel9 +47
  • RHSA-2026:86891 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 3.5.2 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.5 registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-cli-rhel9 +47
Show 1 more Red Hat advisories
  • RHSA-2026:84734 Released 2026-10-19 · Red Hat rating Critical
    RHOAI 3.4.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-ai-gateway-payload-processing-rhel9, registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-autorag-rhel9 +47

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift AI 2.25Fixed RHSA-2026:87410
Red Hat OpenShift AI 3.4Fixed RHSA-2026:84734
Red Hat OpenShift AI 3.5Fixed RHSA-2026:86891
Red Hat OpenShift Dev Spaces 3.31Fixed RHSA-2026:90321
Not affected: 4 products
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift AI 3.5
  • Red Hat OpenShift Dev Spaces 3.31

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-85124
  2. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  3. 2026-10-20 Fix available: Red Hat OpenShift AI 3.4 · Red Hat
  4. 2026-10-22 Fix available: RHSA-2026:86891 · Red Hat
  5. 2026-10-22 Fix available: RHSA-2026:87410 · Red Hat
  6. 2026-10-23 Fix available: Red Hat OpenShift AI 2.25, Red Hat OpenShift AI 3.5 · Red Hat
  7. 2026-10-29 Fix available: Red Hat OpenShift Dev Spaces 3.31 · Red Hat
  8. 2026-10-30 Fix available: RHSA-2026:90321 · Red Hat

References

Advisory 2

  • TI-2026-26177 @fastify/reply-from vulnerable to connection header abuse enabling stripping of proxy-added headers CVSS 4.0CRITICAL 9.0
  • TI-2026-13487 @fastify/http-proxy vulnerable to prefix escape via URL-encoded characters CVSS 3.1CRITICAL 10.0
  • TI-2026-13153 @fastify/http-proxy vulnerable to prefix escape via WebSocket path traversal CVSS 3.1CRITICAL 10.0

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences