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TI-2026-35951 Aliases CVE-2026-48595GHSA-9m9w-gxf7-rh8m

Authorization header leaks to third-party origin on cross-origin redirect in Tesla.Middleware.FollowRedirects

Priority HIGH 69CWE-178Published · Updated

Key facts

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

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

Summary

Improper Handling of Case Sensitivity vulnerability in elixir-tesla tesla allows credential leakage to a third-party origin on cross-origin redirects. Tesla.Middleware.FollowRedirects strips security-sensitive headers on cross-origin redirects using a case-sensitive string comparison against a lowercase filter list (@filter_headers ["authorization", "host"]). HTTP header names are case-insensitive per RFC 7230, but Tesla preserves header keys verbatim as supplied by the caller without normalizing case. A header set as {"Authorization", "Bearer …"} (the RFC 7235 canonical casing used by virtually all HTTP libraries and documentation) does not match the lowercase filter entry and is forwarded to the redirect destination. An attacker who can control or influence a Location: response seen by the client (via their own endpoint, a redirect-open upstream, or a compromised origin) receives the bearer token or other Authorization material on the cross-origin request. This issue affects tesla: from 1.4.0 before 1.18.3.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00487 42nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed tesla (elixir-tesla): 1.18.3tesla (Hex): 1.18.3

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
elixir-teslatesla1.4.0 to before 1.18.31.18.3Patch availableCNA
—tesla (Hex)0.6.0 to before 1.18.31.18.3Patch availableGHSA-9m9w-gxf7-rh8m
  • tesla Vendorelixir-tesla Affected 1.4.0 to before 1.18.3 Fixed in 1.18.3 Patch available CNA
  • tesla (Hex) Vendor— Affected 0.6.0 to before 1.18.3 Fixed in 1.18.3 Patch available GHSA-9m9w-gxf7-rh8m

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:elixir-tesla:tesla:*:*:*:*:*:*:*:*1.4.0 to before 1.18.3Vulnerableelixir-tesla
  • cpe:2.3:a:elixir-tesla:tesla:*:*:*:*:*:*:*:* Versions 1.4.0 to before 1.18.3 Vulnerable ·elixir-tesla

Remediation

  • Fix · CNA tesla (elixir-tesla) Fixed in 1.18.3
  • Fix · GHSA-9m9w-gxf7-rh8m tesla (Hex) Fixed in 1.18.3 Advisory →

Fixed in the same release

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

  • Release ·

    elixir-tesla tesla 1.18.3

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

    Other records, highest priority first

    • TI-2026-35953 Atom table exhaustion via untrusted URL scheme in Tesla.Adapter.MintPriority HIGH 69
    • TI-2026-35954 CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injectionPriority MEDIUM 44
    • TI-2026-35952 CRLF injection in Tesla.Multipart.add_content_type_param/2 allows HTTP header injectionPriority MEDIUM 44
    Show all 5 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-48595
  2. 2026-10-03 Alias added: GHSA-9m9w-gxf7-rh8m
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

Exploit 1

Patch 1

Advisory 3

Other 2

  • TI-2026-35953 Atom table exhaustion via untrusted URL scheme in Tesla.Adapter.Mint CVSS 4.0HIGH 8.2
  • TI-2026-35954 CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection CVSS 4.0LOW 2.1
  • TI-2026-35952 CRLF injection in Tesla.Multipart.add_content_type_param/2 allows HTTP header injection CVSS 4.0LOW 2.1
  • TI-2026-35950 Decompression bomb in Tesla.Middleware.DecompressResponse and Tesla.Middleware.Compression CVSS 4.0HIGH 8.2

Sources

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