CVE-2026-12143 (GCVE-0-2026-12143)

Vulnerability from cvelistv5 – Published: 2026-06-12 18:01 – Updated: 2026-06-12 19:04
VLAI
Title
form-data does not escape CR/LF/quote in multipart field names and filenames (CRLF injection)
Summary
form-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
References
Impacted products
Vendor Product Version
form-data form-data Affected: 0 , < 2.5.6 (semver)
Affected: 3.0.0 , < 3.0.5 (semver)
Affected: 4.0.0 , < 4.0.6 (semver)
Create a notification for this product.
Credits
yueyueL (https://github.com/yueyueL) LJHarb (https://github.com/LJHarb) LJHarb (https://github.com/LJHarb)
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-12143",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-12T19:04:40.604029Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-12T19:04:44.024Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://www.npmjs.com/package/form-data",
          "defaultStatus": "unaffected",
          "packageName": "form-data",
          "product": "form-data",
          "programFiles": [
            "lib/form_data.js"
          ],
          "repo": "https://github.com/form-data/form-data",
          "vendor": "form-data",
          "versions": [
            {
              "lessThan": "2.5.6",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.0.5",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "4.0.6",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "yueyueL (https://github.com/yueyueL)"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "LJHarb (https://github.com/LJHarb)"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "LJHarb (https://github.com/LJHarb)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eform-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (\") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `\"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.\u003c/p\u003e"
            }
          ],
          "value": "form-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (\") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `\"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "exploitMaturity": "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:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "Application uses attacker-controlled input as a multipart field name or filename and forwards the generated request to a trusted backend."
            }
          ]
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-93",
              "description": "CWE-93: Improper Neutralization of CRLF Sequences (\u0027CRLF Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-12T18:01:30.362Z",
        "orgId": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
        "shortName": "harborist"
      },
      "references": [
        {
          "name": "GHSA-hmw2-7cc7-3qxx",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx"
        },
        {
          "name": "Fix commit (4.0.6)",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/form-data/form-data/commit/64190db548c0179e37206858e39f27cf513e9435"
        },
        {
          "name": "Fix commit (3.0.5)",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/form-data/form-data/commit/be3f3cf553978bac15a5182f1f3c3d2d38ccf229"
        },
        {
          "name": "Fix commit (2.5.6)",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/form-data/form-data/commit/c7133499c2ee1b80c678e411244f4442bf902045"
        },
        {
          "name": "npm: form-data",
          "tags": [
            "product"
          ],
          "url": "https://www.npmjs.com/package/form-data"
        },
        {
          "name": "CWE-93",
          "tags": [
            "technical-description"
          ],
          "url": "https://cwe.mitre.org/data/definitions/93.html"
        },
        {
          "name": "WHATWG HTML: multipart/form-data encoding algorithm",
          "tags": [
            "technical-description"
          ],
          "url": "https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#multipart-form-data"
        }
      ],
      "title": "form-data does not escape CR/LF/quote in multipart field names and filenames (CRLF injection)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
    "assignerShortName": "harborist",
    "cveId": "CVE-2026-12143",
    "datePublished": "2026-06-12T18:01:30.362Z",
    "dateReserved": "2026-06-12T17:33:29.185Z",
    "dateUpdated": "2026-06-12T19:04:44.024Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-12143\",\"sourceIdentifier\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\",\"published\":\"2026-06-12T19:16:26.560\",\"lastModified\":\"2026-06-12T20:16:44.800\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"form-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (\\\") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `\\\"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.\"}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/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\",\"baseScore\":8.7,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-93\"}]}],\"references\":[{\"url\":\"https://cwe.mitre.org/data/definitions/93.html\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://github.com/form-data/form-data/commit/64190db548c0179e37206858e39f27cf513e9435\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://github.com/form-data/form-data/commit/be3f3cf553978bac15a5182f1f3c3d2d38ccf229\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://github.com/form-data/form-data/commit/c7133499c2ee1b80c678e411244f4442bf902045\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#multipart-form-data\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://www.npmjs.com/package/form-data\",\"source\":\"7ffcee3d-2c14-4c3e-b844-86c6a321a158\"},{\"url\":\"https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-12143\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-12T19:04:40.604029Z\"}}}], \"references\": [{\"url\": \"https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-12T19:03:56.430Z\"}}], \"cna\": {\"title\": \"form-data does not escape CR/LF/quote in multipart field names and filenames (CRLF injection)\", \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"yueyueL (https://github.com/yueyueL)\"}, {\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"LJHarb (https://github.com/LJHarb)\"}, {\"lang\": \"en\", \"type\": \"coordinator\", \"value\": \"LJHarb (https://github.com/LJHarb)\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 8.7, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"Application uses attacker-controlled input as a multipart field name or filename and forwards the generated request to a trusted backend.\"}]}, {\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"repo\": \"https://github.com/form-data/form-data\", \"vendor\": \"form-data\", \"product\": \"form-data\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"2.5.6\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"3.0.0\", \"lessThan\": \"3.0.5\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"4.0.0\", \"lessThan\": \"4.0.6\", \"versionType\": \"semver\"}], \"packageName\": \"form-data\", \"programFiles\": [\"lib/form_data.js\"], \"collectionURL\": \"https://www.npmjs.com/package/form-data\", \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/form-data/form-data/security/advisories/GHSA-hmw2-7cc7-3qxx\", \"name\": \"GHSA-hmw2-7cc7-3qxx\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://github.com/form-data/form-data/commit/64190db548c0179e37206858e39f27cf513e9435\", \"name\": \"Fix commit (4.0.6)\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/form-data/form-data/commit/be3f3cf553978bac15a5182f1f3c3d2d38ccf229\", \"name\": \"Fix commit (3.0.5)\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/form-data/form-data/commit/c7133499c2ee1b80c678e411244f4442bf902045\", \"name\": \"Fix commit (2.5.6)\", \"tags\": [\"patch\"]}, {\"url\": \"https://www.npmjs.com/package/form-data\", \"name\": \"npm: form-data\", \"tags\": [\"product\"]}, {\"url\": \"https://cwe.mitre.org/data/definitions/93.html\", \"name\": \"CWE-93\", \"tags\": [\"technical-description\"]}, {\"url\": \"https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#multipart-form-data\", \"name\": \"WHATWG HTML: multipart/form-data encoding algorithm\", \"tags\": [\"technical-description\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"form-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (\\\") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `\\\"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eform-data is a library for creating readable multipart/form-data streams. In versions through 4.0.5, the `field` argument to `FormData#append` and the `filename` option are concatenated verbatim into the `Content-Disposition` header without escaping carriage return (CR), line feed (LF), or double-quote (\\\") characters. An application that passes attacker-controlled data as a field name or filename (for example, an API gateway that turns JSON object keys into multipart field names) allows the attacker to terminate the header line and inject additional headers, or to smuggle entire additional multipart parts, into the request the application forwards to a backend. This can let the attacker add or override form fields (e.g. set `is_admin=true`) seen by the downstream parser. This is an instance of CWE-93 (CRLF injection). The fix escapes CR, LF, and `\\\"` as `%0D`, `%0A`, and `%22` in field names and filenames, matching the serialization browsers use per the WHATWG HTML multipart/form-data encoding algorithm. Exploitation requires the consuming application to use untrusted input as a field name or filename; applications that use only fixed/trusted field names are not affected. Fixed in 2.5.6, 3.0.5, and 4.0.6.\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-93\", \"description\": \"CWE-93: Improper Neutralization of CRLF Sequences (\u0027CRLF Injection\u0027)\"}]}], \"providerMetadata\": {\"orgId\": \"7ffcee3d-2c14-4c3e-b844-86c6a321a158\", \"shortName\": \"harborist\", \"dateUpdated\": \"2026-06-12T18:01:30.362Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-12143\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-12T19:04:44.024Z\", \"dateReserved\": \"2026-06-12T17:33:29.185Z\", \"assignerOrgId\": \"7ffcee3d-2c14-4c3e-b844-86c6a321a158\", \"datePublished\": \"2026-06-12T18:01:30.362Z\", \"assignerShortName\": \"harborist\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.