FKIE_CVE-2026-89044

Vulnerability from fkie_nvd - Published: 2026-09-10 18:18 - Updated: 2026-09-18 18:17
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Summary
Netty versions 4.1.133.Final through 4.1.137.Final and 4.2.13.Final through 4.2.17.Final fail to properly validate the final transfer coding in the Transfer-Encoding header, allowing attackers to smuggle requests by using malformed encoding declarations. Attackers can split Transfer-Encoding headers across multiple lines or use values like 'chunked, xchunked' to bypass validation and decode messages as chunked when the final coding is not chunked, enabling request smuggling attacks.
References
disclosure@vulncheck.comhttps://github.com/netty/nettyProduct
disclosure@vulncheck.comhttps://github.com/netty/netty/blob/netty-4.1.137.Final/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java#L866Product
disclosure@vulncheck.comhttps://github.com/netty/netty/commit/640d4d3324f7b811a4903d0730c8ccb35500500cPatch
disclosure@vulncheck.comhttps://github.com/netty/netty/commit/ca87393b0e9e13c493d213a268e727a6d44e1585Patch
disclosure@vulncheck.comhttps://github.com/netty/netty/releases/tag/netty-4.1.138.FinalRelease Notes
disclosure@vulncheck.comhttps://github.com/netty/netty/releases/tag/netty-4.2.18.FinalRelease Notes
disclosure@vulncheck.comhttps://github.com/netty/netty/security/advisories/GHSA-hcvj-94mj-jp5cExploit, Vendor Advisory
disclosure@vulncheck.comhttps://www.vulncheck.com/advisories/netty-4.1.133-final-through-4.1.137-final-and-4.2.13-final-through-4.2.17-final-http-request-smuggling-via-transfer-encodingPatch, Third Party Advisory
Impacted products
Vendor Product Version
netty netty *
netty netty *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo1.maven.org/maven2/io/netty/netty-codec-http/",
          "defaultStatus": "unaffected",
          "packageURL": "pkg:maven/io.netty/netty-codec-http",
          "product": "netty",
          "repo": "https://github.com/netty/netty",
          "vendor": "netty",
          "versions": [
            {
              "lessThan": "4.1.138.Final",
              "status": "affected",
              "version": "4.1.133.Final",
              "versionType": "custom"
            },
            {
              "lessThan": "4.2.18.Final",
              "status": "affected",
              "version": "4.2.13.Final",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "disclosure@vulncheck.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D2ABD6AF-82BD-40D0-9A03-4101220F39CC",
              "versionEndExcluding": "4.1.138",
              "versionStartIncluding": "4.1.133",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "EC21FA2A-C386-4134-A447-92616A930370",
              "versionEndExcluding": "4.2.18",
              "versionStartIncluding": "4.2.13",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Netty versions 4.1.133.Final through 4.1.137.Final and 4.2.13.Final through 4.2.17.Final fail to properly validate the final transfer coding in the Transfer-Encoding header, allowing attackers to smuggle requests by using malformed encoding declarations. Attackers can split Transfer-Encoding headers across multiple lines or use values like \u0027chunked, xchunked\u0027 to bypass validation and decode messages as chunked when the final coding is not chunked, enabling request smuggling attacks."
    }
  ],
  "id": "CVE-2026-89044",
  "lastModified": "2026-09-18T18:17:39.213",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "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:N/PR:N/UI:N/VC:L/VI:L/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": "LOW",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-89044",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-18T17:11:17.626681Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-10T18:18:16.243",
  "references": [
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Product"
      ],
      "url": "https://github.com/netty/netty"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Product"
      ],
      "url": "https://github.com/netty/netty/blob/netty-4.1.137.Final/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java#L866"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/netty/netty/commit/640d4d3324f7b811a4903d0730c8ccb35500500c"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/netty/netty/commit/ca87393b0e9e13c493d213a268e727a6d44e1585"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/netty/netty/releases/tag/netty-4.1.138.Final"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/netty/netty/releases/tag/netty-4.2.18.Final"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/netty/netty/security/advisories/GHSA-hcvj-94mj-jp5c"
    },
    {
      "source": "disclosure@vulncheck.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://www.vulncheck.com/advisories/netty-4.1.133-final-through-4.1.137-final-and-4.2.13-final-through-4.2.17-final-http-request-smuggling-via-transfer-encoding"
    }
  ],
  "sourceIdentifier": "disclosure@vulncheck.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-444"
        }
      ],
      "source": "disclosure@vulncheck.com",
      "type": "Secondary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.