FKIE_CVE-2026-89422

Vulnerability from fkie_nvd - Published: 2026-09-22 09:17 - Updated: 2026-09-22 19:09
Severity
9.3 (Critical) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Summary
Key Exchange without Entity Authentication vulnerability in Erlang/OTP ssl allows a peer that answers a TLS 1.3 client connection to impersonate the intended server. A pre_shared_key extension in the ServerHello that the client never offered causes the client to complete the handshake without validating the server's certificate, so ssl:connect returns {ok, Socket} against a peer holding no certificate, no private key and no prior session. tls_client_connection_1_3:handle_server_hello/2 passes the received extension to tls_gen_connection_1_3:handle_resumption/2, which sets resumption = true on its mere presence without checking that the client offered a PSK. tls_handshake_1_3:get_pre_shared_key/4 meanwhile falls back to the all-zero "no PSK" value and keys the handshake with the ordinary non-PSK schedule, so the attacker's own ephemeral key suffices. The resumption flag then routes maybe_resumption/1 straight to wait_finished, skipping the certificate-handling states, so certificate path validation, verify_fun, hostname verification, partial_chain, CRL checking and OCSP stapling are all bypassed. The default client configuration is affected; clients restricted to TLS 1.2 are not. This issue affects OTP from OTP 22.2 before OTP 27.3.4.18, OTP 28.5.0.7, and OTP 29.1.1, corresponding to ssl from 9.5 before 11.2.12.13, 11.6.0.6, and 11.7.7.
References
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://cna.erlef.org/cves/CVE-2026-89422.html
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/erlang/otp/commit/21b8a1b0ad0adf200682b3854bc50114ab2b8c62
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/erlang/otp/commit/98c66c858113949c4262d26cd7d426c4b09d2b35
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/erlang/otp/commit/afec5156361bb50d3607c7c1a453c19b9149b324
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/erlang/otp/commit/fd1d9d07fc92ec0d59f96dfb66182195882bb7dd
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/erlang/otp/security/advisories/GHSA-rgxr-4g4w-j875
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://osv.dev/vulnerability/EEF-CVE-2026-89422
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://www.erlang.org/doc/system/versions.html#order-of-versions
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "tls_client_connection_1_3",
            "tls_gen_connection_1_3",
            "tls_handshake_1_3"
          ],
          "packageName": "otp",
          "packageURL": "pkg:software-id/erlang.org/otp",
          "product": "OTP",
          "programFiles": [
            "lib/ssl/src/tls_client_connection_1_3.erl",
            "lib/ssl/src/tls_gen_connection_1_3.erl",
            "lib/ssl/src/tls_handshake_1_3.erl"
          ],
          "programRoutines": [
            {
              "name": "tls_client_connection_1_3:handle_server_hello/2"
            },
            {
              "name": "tls_client_connection_1_3:handle_encrypted_extensions/2"
            },
            {
              "name": "tls_client_connection_1_3:maybe_resumption/1"
            },
            {
              "name": "tls_gen_connection_1_3:handle_resumption/2"
            },
            {
              "name": "tls_handshake_1_3:get_pre_shared_key/4"
            }
          ],
          "vendor": "Erlang",
          "versions": [
            {
              "changes": [
                {
                  "at": "27.3.4.18",
                  "status": "unaffected"
                },
                {
                  "at": "28.5.0.7",
                  "status": "unaffected"
                },
                {
                  "at": "29.1.1",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "22.2",
              "versionType": "otp"
            }
          ]
        },
        {
          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "tls_client_connection_1_3",
            "tls_gen_connection_1_3",
            "tls_handshake_1_3"
          ],
          "packageName": "ssl",
          "packageURL": "pkg:otp/ssl?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp\u0026vcs_url=git%2Bhttps:%2F%2Fgithub.com%2Ferlang%2Fotp.git",
          "product": "OTP",
          "programFiles": [
            "src/tls_client_connection_1_3.erl",
            "src/tls_gen_connection_1_3.erl",
            "src/tls_handshake_1_3.erl"
          ],
          "programRoutines": [
            {
              "name": "tls_client_connection_1_3:handle_server_hello/2"
            },
            {
              "name": "tls_client_connection_1_3:handle_encrypted_extensions/2"
            },
            {
              "name": "tls_client_connection_1_3:maybe_resumption/1"
            },
            {
              "name": "tls_gen_connection_1_3:handle_resumption/2"
            },
            {
              "name": "tls_handshake_1_3:get_pre_shared_key/4"
            }
          ],
          "repo": "https://github.com/erlang/otp",
          "vendor": "Erlang",
          "versions": [
            {
              "changes": [
                {
                  "at": "11.2.12.13",
                  "status": "unaffected"
                },
                {
                  "at": "11.6.0.6",
                  "status": "unaffected"
                },
                {
                  "at": "11.7.7",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "9.5",
              "versionType": "otp"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "tls_client_connection_1_3",
            "tls_gen_connection_1_3",
            "tls_handshake_1_3"
          ],
          "packageName": "erlang/otp",
          "packageURL": "pkg:github/erlang/otp",
          "product": "OTP",
          "programFiles": [
            "lib/ssl/src/tls_client_connection_1_3.erl",
            "lib/ssl/src/tls_gen_connection_1_3.erl",
            "lib/ssl/src/tls_handshake_1_3.erl"
          ],
          "programRoutines": [
            {
              "name": "tls_client_connection_1_3:handle_server_hello/2"
            },
            {
              "name": "tls_client_connection_1_3:handle_encrypted_extensions/2"
            },
            {
              "name": "tls_client_connection_1_3:maybe_resumption/1"
            },
            {
              "name": "tls_gen_connection_1_3:handle_resumption/2"
            },
            {
              "name": "tls_handshake_1_3:get_pre_shared_key/4"
            }
          ],
          "repo": "https://github.com/erlang/otp",
          "vendor": "Erlang",
          "versions": [
            {
              "changes": [
                {
                  "at": "afec5156361bb50d3607c7c1a453c19b9149b324",
                  "status": "unaffected"
                },
                {
                  "at": "98c66c858113949c4262d26cd7d426c4b09d2b35",
                  "status": "unaffected"
                },
                {
                  "at": "fd1d9d07fc92ec0d59f96dfb66182195882bb7dd",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "21b8a1b0ad0adf200682b3854bc50114ab2b8c62",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Key Exchange without Entity Authentication vulnerability in Erlang/OTP ssl allows a peer that answers a TLS 1.3 client connection to impersonate the intended server. A pre_shared_key extension in the ServerHello that the client never offered causes the client to complete the handshake without validating the server\u0027s certificate, so ssl:connect returns {ok, Socket} against a peer holding no certificate, no private key and no prior session.\n\ntls_client_connection_1_3:handle_server_hello/2 passes the received extension to tls_gen_connection_1_3:handle_resumption/2, which sets resumption = true on its mere presence without checking that the client offered a PSK. tls_handshake_1_3:get_pre_shared_key/4 meanwhile falls back to the all-zero \"no PSK\" value and keys the handshake with the ordinary non-PSK schedule, so the attacker\u0027s own ephemeral key suffices. The resumption flag then routes maybe_resumption/1 straight to wait_finished, skipping the certificate-handling states, so certificate path validation, verify_fun, hostname verification, partial_chain, CRL checking and OCSP stapling are all bypassed. The default client configuration is affected; clients restricted to TLS 1.2 are not.\n\nThis issue affects OTP from OTP\u00a022.2 before OTP\u00a027.3.4.18, OTP\u00a028.5.0.7, and OTP\u00a029.1.1, corresponding to ssl from 9.5 before 11.2.12.13, 11.6.0.6, and 11.7.7."
    }
  ],
  "id": "CVE-2026-89422",
  "lastModified": "2026-09-22T19:09:32.273",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 9.3,
          "baseSeverity": "CRITICAL",
          "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:H/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-89422",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-22T13:08:04.474621Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-22T09:17:05.540",
  "references": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://cna.erlef.org/cves/CVE-2026-89422.html"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/erlang/otp/commit/21b8a1b0ad0adf200682b3854bc50114ab2b8c62"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/erlang/otp/commit/98c66c858113949c4262d26cd7d426c4b09d2b35"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/erlang/otp/commit/afec5156361bb50d3607c7c1a453c19b9149b324"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/erlang/otp/commit/fd1d9d07fc92ec0d59f96dfb66182195882bb7dd"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/erlang/otp/security/advisories/GHSA-rgxr-4g4w-j875"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-89422"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://www.erlang.org/doc/system/versions.html#order-of-versions"
    }
  ],
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-322"
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary"
    }
  ]
}



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.



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.