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TI-2026-57044 Aliases CVE-2026-82726

AshPhoenix get_subdomain maps a crafted or differently-cased Host header to an arbitrary tenant

Priority MEDIUM 61CWE-178Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Permissive Regular Expression vulnerability in ash-project ash_phoenix lets a remote client select the tenant an Ash application uses, or degrade the request, by sending a crafted Host header. AshPhoenix.Helpers.get_subdomain/2 stripped the root domain with String.replace(host, ~r/.?#{root_host}/, ""). The root host was interpolated raw, so each . became a wildcard and any metacharacter a pattern, and the replace was global and unanchored, so a match was removed from anywhere in the string. With root_host example.com, Host: foo.exampleXcom.attacker.net returned the tenant foo.attacker.net. A metacharacter-bearing or nil root host degraded the pattern or raised on every request. The comparison was also case-sensitive, so TENANT.EXAMPLE.COM and EXAMPLE.COM slipped past the root-host allowlist. conn.host comes from the client Host header. The fix matches the root host case-insensitively and only as an exact trailing suffix. This issue affects ash_phoenix: from 2.1.26 before 2.3.25.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00524 44th percentileScored 2026-11-07
Fix Fixed ash_phoenix (ash-project): 2.3.25

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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
ash-projectash_phoenix2.1.26 to before 2.3.252.3.25Patch availableCNA
  • ash_phoenix Vendorash-project Affected 2.1.26 to before 2.3.25 Fixed in 2.3.25 Patch available CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:ash-project:ash_phoenix:*:*:*:*:*:*:*:*———
  • cpe:2.3:a:ash-project:ash_phoenix:*:*:*:*:*:*:*:* Versions — — ·—

Remediation

  • Fix · CNA ash_phoenix (ash-project) Fixed in 2.3.25

Fixed in the same release

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

  • Release ·

    ash-project ash_phoenix 2.3.25

    4 records Highest priority Priority HIGH 1 HIGH, 2 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-57042 Broken access control in AshPhoenix SubdomainHook via a nil tenant in handle_subdomainPriority HIGH 68
    • TI-2026-57045 AshPhoenix Form.Auto leaks submitted params in an unknown _union_type error messagePriority MEDIUM 45
    • TI-2026-57043 AshPhoenix FilterForm allows filtering across non-public relationships, disclosing private related dataPriority LOW 12
    Show all 4 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-82726

References

Patch 1

Advisory 1

Other 2

  • TI-2026-56298 Query-complexity limit bypass via first/last pagination arguments in AshGraphql enables denial of service CVSS 4.0HIGH 8.7
  • TI-2026-52572 Unbounded atom creation from client-supplied RPC field names in AshTypescript field formatter CVSS 4.0HIGH 8.7
  • TI-2026-57010 Path traversal in AshAdmin file uploads via unsanitized client filename CVSS 4.0HIGH 8.3
  • TI-2026-26840 Ash Framework: Ash.Type.Module.cast_input/2 atom exhaustion via unchecked Module.concat allows BEAM VM crash CVSS 4.0HIGH 8.2
  • TI-2026-54252 EEx template evaluation of prompt content in AshAi enables remote code execution CVSS 4.0HIGH 8.9
  • TI-2026-54208 Stored XSS in AshAdmin relationship typeahead via unescaped label_field content CVSS 4.0HIGH 8.4
See all 90 →

Sources

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