Tesla.Multipart.part_headers_for_disposition/1 interpolates each disposition parameter as #{k}=\"#{v}\" with no validation of CR (\\r), LF (\\n), or double-quote characters. The values come verbatim from the caller via Tesla.Multipart.add_field/4 (the name parameter), Tesla.Multipart.add_file/3, and Tesla.Multipart.add_file_content/4 (both the filename parameter and other disposition opts). A \" in the value closes the quoted parameter early; a \\r\\n ends the Content-Disposition header line and starts a new part header (such as a forged Content-Type), or, after a second \\r\\n, ends the entire part header block and prepends bytes to the part body. The default-filename path in add_file/3 derives the filename via Path.basename/1, which does not strip CR or LF, so any application forwarding a partially-attacker-controlled file path inherits the same issue.
This issue affects tesla: from 0.8.0 before 1.18.3.
" } ], "value": "Improper Encoding or Escaping of Output vulnerability in elixir-tesla tesla allows multipart part header injection via unescaped Content-Disposition parameter values.\n\nTesla.Multipart.part_headers_for_disposition/1 interpolates each disposition parameter as #{k}=\"#{v}\" with no validation of CR (\\r), LF (\\n), or double-quote characters. The values come verbatim from the caller via Tesla.Multipart.add_field/4 (the name parameter), Tesla.Multipart.add_file/3, and Tesla.Multipart.add_file_content/4 (both the filename parameter and other disposition opts). A \" in the value closes the quoted parameter early; a \\r\\n ends the Content-Disposition header line and starts a new part header (such as a forged Content-Type), or, after a second \\r\\n, ends the entire part header block and prepends bytes to the part body. The default-filename path in add_file/3 derives the filename via Path.basename/1, which does not strip CR or LF, so any application forwarding a partially-attacker-controlled file path inherits the same issue.\n\nThis issue affects tesla: from 0.8.0 before 1.18.3." } ], "impacts": [ { "capecId": "CAPEC-105", "descriptions": [ { "lang": "en", "value": "CAPEC-105 HTTP Request Splitting" } ] } ], "metrics": [ { "cvssV4_0": { "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "LOCAL", "baseScore": 2.1, "baseSeverity": "LOW", "privilegesRequired": "NONE", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "LOW", "userInteraction": "NONE", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE" }, "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ] } ], "problemTypes": [ { "descriptions": [ { "cweId": "CWE-116", "description": "CWE-116 Improper Encoding or Escaping of Output", "lang": "en", "type": "CWE" } ] } ], "providerMetadata": { "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-06-04T04:45:23.895Z" }, "references": [ { "tags": [ "vendor-advisory", "related" ], "url": "https://github.com/elixir-tesla/tesla/security/advisories/GHSA-28jh-g32x-v9v4" }, { "tags": [ "related" ], "url": "https://cna.erlef.org/cves/CVE-2026-48598.html" }, { "tags": [ "related" ], "url": "https://osv.dev/vulnerability/EEF-CVE-2026-48598" }, { "tags": [ "patch" ], "url": "https://github.com/elixir-tesla/tesla/commit/bb1a2c3da2775924d96e3db8e315dcc4d5d2246e" } ], "source": { "discovery": "EXTERNAL" }, "title": "CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection", "workarounds": [ { "lang": "en", "supportingMedia": [ { "base64": false, "type": "text/html", "value": "Validate disposition parameter values before passing them to Tesla.Multipart.add_field/4, Tesla.Multipart.add_file/3, or Tesla.Multipart.add_file_content/4, rejecting any value that contains \\r, \\n, or \"." } ], "value": "Validate disposition parameter values before passing them to Tesla.Multipart.add_field/4, Tesla.Multipart.add_file/3, or Tesla.Multipart.add_file_content/4, rejecting any value that contains \\r, \\n, or \"." } ], "x_generator": { "engine": "cvelib 1.8.0" } }, "adp": [ { "references": [ { "url": "https://github.com/elixir-tesla/tesla/security/advisories/GHSA-28jh-g32x-v9v4", "tags": [ "exploit" ] } ], "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-06-03T14:58:39.064613Z", "id": "CVE-2026-48598", "options": [ { "Exploitation": "poc" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-03T15:00:21.959Z" } } ] } }