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TI-2026-76132 Aliases CVE-2026-111927GHSA-47cv-h282-xh6p

Hostname prefix match in Coder workspace proxy leaks API keys

Priority LOW 39CWE-522Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Passive
Attack complexity
High
Attack requirements
Present
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-522.

Summary

Coder versions before 2.29.20, 2.33.0 before 2.33.12, 2.34.0 before 2.34.8, and 2.35.0 before 2.35.4 contain an improper hostname validation flaw (CWE-522) in GetWorkspaceProxyByHostname. Its SIMILAR TO pattern performs a prefix match, so any domain that is a string prefix of a workspace proxy access URL is trusted as a proxy. An attacker who owns such a domain can lure an authenticated victim to a crafted auth-redirect link, capture the redirected application_connect API key, and replay it to access the victim's workspace apps.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Coder before 2.29.20, 2.33.0 before 2.33.12, 2.34.0 before 2.34.8, and 2.35.0 before 2.35.4 contains an improper hostname validation flaw in GetWorkspaceProxyByHostname whose SIMILAR TO pattern performs a prefix match, so any domain that is a string prefix of a workspace-proxy access URL is trusted as a proxy. Attackers owning such a domain can lure an authenticated victim to a crafted /api/v2/applications/auth-redirect link, capture the redirected application_connect API key, and replay it to access the victim's workspace apps.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00205 10th percentileScored 2026-11-07
Fix Fixed coder (coder): 2.35.4, 2.34.8, 2.33.12 +1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
codercoder2.35.0 to before 2.35.42.35.4Patch availableCNA
codercoder2.34.0 to before 2.34.82.34.8Patch availableCNA
codercoder2.33.0 to before 2.33.122.33.12Patch availableCNA
codercoderbefore 2.29.202.29.20Patch availableCNA
  • coder Vendorcoder Affected 2.35.0 to before 2.35.4 Fixed in 2.35.4 Patch available CNA
  • coder Vendorcoder Affected 2.34.0 to before 2.34.8 Fixed in 2.34.8 Patch available CNA
  • coder Vendorcoder Affected 2.33.0 to before 2.33.12 Fixed in 2.33.12 Patch available CNA
  • coder Vendorcoder Affected before 2.29.20 Fixed in 2.29.20 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:coder:coder:*:*:*:*:*:*:*:*——coder
  • cpe:2.3:a:coder:coder:*:*:*:*:*:*:*:* Versions — — ·coder

Remediation

Upgrade Coder to version 2.29.20, 2.33.12, 2.34.8, or 2.35.4.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA coder (coder) Fixed in 2.35.4
  • Fix · CNA coder (coder) Fixed in 2.34.8
  • Fix · CNA coder (coder) Fixed in 2.33.12
  • Fix · CNA coder (coder) Fixed in 2.29.20

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    coder 2.34.8

    6 records Highest priority Priority LOW 6 LOW

    Other records, highest priority first

    • TI-2026-76134 Coder bypass exposes other organizations' Terraform module filesPriority LOW 26
    • TI-2026-76136 Open redirect in Coder via workspace app proxyPriority LOW 23
    • TI-2026-76135 Information disclosure in Coder workspace ACL endpointPriority LOW 23
    Show all 6 records →

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-111927
  2. 2026-10-18 Alias added: GHSA-47cv-h282-xh6p
  3. 2026-10-18 Priority changed: MEDIUM → LOW
  4. 2026-10-21 CISA SSVC decision points changed

References

Advisory 1

  • TI-2025-29799 code-server session cookie can be extracted by having user visit specially crafted proxy URL CVSS 3.1HIGH 8.3
  • TI-2025-37344 AgentAPI exposed user chat history via a DNS rebinding attack CVSS 3.1MEDIUM 6.5
  • TI-2026-34071 Coder: PKCS#7 signature bypass in Azure instance identity allows unauthenticated agent token theft CVSS 3.1CRITICAL 9.1
  • TI-2026-32394 Coder vulnerable to workspace auto-creation via crafted URL parameters without user consent CVSS 3.1HIGH 8.8
  • TI-2026-27585 Code Extension Marketplace has a Zip Slip Path Traversal CVSS 4.0HIGH 8.7
  • TI-2024-18523 Coder's OIDC authentication allows email with partially matching domain to register CVSS 3.1HIGH 8.2
See all 42 →

Sources

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