CVE-2026-94440 (GCVE-0-2026-94440)

Vulnerability from cvelistv5 – Published: 2026-10-08 22:53 – Updated: 2026-10-08 22:53
VLAI
Title
Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart
Summary
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
Severity
No CVSS data available.
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
Go CNA under the Google root
CNA scorecard E 42/100 over 75 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Go standard library net/textproto Affected: 0 , < 1.26.9 (semver)
Affected: 1.27.0-0 , < 1.27.2 (semver)
guessed Create a notification for this product.
Go standard library mime/multipart Affected: 0 , < 1.26.9 (semver)
Affected: 1.27.0-0 , < 1.27.2 (semver)
guessed Create a notification for this product.
Credits
Jakub Ciolek (https://ciolek.dev)
Show details on NVD website
To clipboard 

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          "packageName": "net/textproto",
          "product": "net/textproto",
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            {
              "name": "readMIMEHeader"
            },
            {
              "name": "Reader.readContinuedLineSlice"
            },
            {
              "name": "Reader.ReadContinuedLine"
            },
            {
              "name": "Reader.ReadContinuedLineBytes"
            },
            {
              "name": "Reader.ReadMIMEHeader"
            }
          ],
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        },
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          "defaultStatus": "unaffected",
          "packageName": "mime/multipart",
          "product": "mime/multipart",
          "programRoutines": [
            {
              "name": "Part.populateHeaders"
            },
            {
              "name": "Reader.readForm"
            },
            {
              "name": "Reader.NextPart"
            },
            {
              "name": "Reader.NextRawPart"
            },
            {
              "name": "Reader.ReadForm"
            }
          ],
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      ],
      "credits": [
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          "value": "Jakub Ciolek (https://ciolek.dev)"
        }
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      "descriptions": [
        {
          "lang": "en",
          "value": "Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes."
        }
      ],
      "problemTypes": [
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          "descriptions": [
            {
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
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            }
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        },
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        },
        {
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      "title": "Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart"
    }
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    "cveId": "CVE-2026-94440",
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    "dateReserved": "2026-09-21T16:43:04.757Z",
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                    "name": "Reader.readForm"
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        "lastModified": "2026-10-08T23:17:04.917",
        "metrics": {},
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        "sourceIdentifier": "security@golang.org",
        "vulnStatus": "Received"
      }
    }
  }
}



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