Vulnerability-Lookup

CVE-2026-48595 (GCVE-0-2026-48595)

Vulnerability from cvelistv5 – Published: 2026-06-02 19:08 – Updated: 2026-06-03 15:59

Title

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

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.

Severity

8.2 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-178 - Improper Handling of Case Sensitivity

Assigner

EEF

References

4 references

URL	Tags
https://github.com/elixir-tesla/tesla/security/ad…	vendor-advisoryrelated
https://cna.erlef.org/cves/CVE-2026-48595.html	related
https://osv.dev/vulnerability/EEF-CVE-2026-48595	related
https://github.com/elixir-tesla/tesla/commit/db96…	patch

Impacted products

2 products

Vendor	Product	Version
elixir-tesla	tesla	Affected: 1.4.0 , < 1.18.3 (semver) cpe:2.3:a:elixir-tesla:tesla::::::::
elixir-tesla	tesla	Affected: 2d937d5813d7cda5cd726f41824985fb655c920f , < db963dba67651b9abd1fc420a1d9679cf6efe182 (git) cpe:2.3:a:elixir-tesla:tesla::::::::

Credits

Peter Ullrich Yordis Prieto Jonatan Männchen

Show details on NVD website

JSON

To clipboard

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An attacker who can control or influence a \u003ctt\u003eLocation:\u003c/tt\u003e response seen by the client (via their own endpoint, a redirect-open upstream, or a compromised origin) receives the bearer token or other \u003ctt\u003eAuthorization\u003c/tt\u003e material on the cross-origin request.\u003c/p\u003e\u003cp\u003eThis issue affects tesla: from 1.4.0 before 1.18.3.\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-178\", \"description\": \"CWE-178 Improper Handling of Case Sensitivity\"}]}], \"configurations\": [{\"lang\": \"en\", \"value\": \"The application must include Tesla.Middleware.FollowRedirects in its Tesla middleware pipeline.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"The application must include \u003ctt\u003eTesla.Middleware.FollowRedirects\u003c/tt\u003e in its Tesla middleware pipeline.\", \"base64\": false}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:elixir-tesla:tesla:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"1.18.3\", \"versionStartIncluding\": \"1.4.0\"}], \"operator\": \"OR\"}], \"operator\": \"AND\"}], \"providerMetadata\": {\"orgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"shortName\": \"EEF\", \"dateUpdated\": \"2026-06-02T19:12:24.989Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-48595\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-03T15:59:54.838Z\", \"dateReserved\": \"2026-05-22T09:36:56.834Z\", \"assignerOrgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"datePublished\": \"2026-06-02T19:08:48.339Z\", \"assignerShortName\": \"EEF\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

FKIE_CVE-2026-48595

Vulnerability from fkie_nvd - Published: 2026-06-02 20:16 - Updated: 2026-06-03 18:16

Severity

8.2 (High) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Summary

References

	URL	Tags
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://cna.erlef.org/cves/CVE-2026-48595.html
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://github.com/elixir-tesla/tesla/commit/db963dba67651b9abd1fc420a1d9679cf6efe182
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://github.com/elixir-tesla/tesla/security/advisories/GHSA-9m9w-gxf7-rh8m
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://osv.dev/vulnerability/EEF-CVE-2026-48595
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/elixir-tesla/tesla/security/advisories/GHSA-9m9w-gxf7-rh8m

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper Handling of Case Sensitivity vulnerability in elixir-tesla tesla allows credential leakage to a third-party origin on cross-origin redirects.\n\nTesla.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 \u2026\"} (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.\n\nThis issue affects tesla: from 1.4.0 before 1.18.3."
    }
  ],
  "id": "CVE-2026-48595",
  "lastModified": "2026-06-03T18:16:29.710",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-06-02T20:16:38.390",
  "references": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://cna.erlef.org/cves/CVE-2026-48595.html"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/elixir-tesla/tesla/commit/db963dba67651b9abd1fc420a1d9679cf6efe182"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/elixir-tesla/tesla/security/advisories/GHSA-9m9w-gxf7-rh8m"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-48595"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/elixir-tesla/tesla/security/advisories/GHSA-9m9w-gxf7-rh8m"
    }
  ],
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-178"
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

CVE-2026-48595 (GCVE-0-2026-48595)

FKIE_CVE-2026-48595

Tags

Sightings

Nomenclature