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CVE-2026-55952

Full vulnerability record from the local CVENow database.

Description

The Erlang/OTP ssl application does not validate that the PSK identity list and binder list carried in a TLS 1.3 ClientHello pre-shared key extension have equal length before passing them to the session ticket handler. In tls_handshake_1_3:handle_pre_shared_key/3, an OfferedPreSharedKeys record with a mismatched number of identities and binders is forwarded directly to tls_server_session_ticket:use/4, which crashes the session ticket handler process. An unauthenticated remote attacker can send a single crafted ClientHello to a TLS 1.3 server with session tickets enabled (stateful or stateless mode) and permanently disrupt session ticket handling on that listener. New TLS 1.3 handshakes complete but subsequently crash when the server attempts to issue a session ticket, effectively making TLS 1.3 unusable on the affected listener until the ssl application is restarted. TLS 1.2 connections are not affected. This issue affects OTP from OTP 22.2 before OTP 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 9.5 before 11.7.3, 11.6.0.3 and 11.2.12.10.

Severity
HIGH
CVSS score
8.2 (v4.0)
Vulnerability status
Modified
Source identifier
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Published
2026-07-02 17:17:03.067000
Last modified
2026-10-25 21:10:00.770000
View original CVE JSON 
{
  "id": "CVE-2026-55952",
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "published": "2026-07-02T17:17:03.067",
  "lastModified": "2026-10-25T21:10:00.770",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Erlang/OTP ssl application does not validate that the PSK identity list and binder list carried in a TLS 1.3 ClientHello pre-shared key extension have equal length before passing them to the session ticket handler. In tls_handshake_1_3:handle_pre_shared_key/3, an OfferedPreSharedKeys record with a mismatched number of identities and binders is forwarded directly to tls_server_session_ticket:use/4, which crashes the session ticket handler process.\n\nAn unauthenticated remote attacker can send a single crafted ClientHello to a TLS 1.3 server with session tickets enabled (stateful or stateless mode) and permanently disrupt session ticket handling on that listener. New TLS 1.3 handshakes complete but subsequently crash when the server attempts to issue a session ticket, effectively making TLS 1.3 unusable on the affected listener until the ssl application is restarted. TLS 1.2 connections are not affected.\n\nThis issue affects OTP from OTP 22.2 before OTP 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 9.5 before 11.7.3, 11.6.0.3 and 11.2.12.10."
    },
    {
      "lang": "es",
      "value": "La aplicación ssl de Erlang/OTP no valida que la lista de identidades PSK y la lista de ’binders’ transportadas en una extensión de clave precompartida de ClientHello de TLS 1.3 tengan la misma longitud antes de pasarlas al gestor de tickets de sesión. En tls_handshake_1_3:handle_pre_shared_key/3, un registro OfferedPreSharedKeys con un número no coincidente de identidades y ’binders’ se reenvía directamente a tls_server_session_ticket:use/4, lo que provoca la caída del proceso del gestor de tickets de sesión.\n\nUn atacante remoto no autenticado puede enviar un único ClientHello manipulado a un servidor TLS 1.3 con tickets de sesión habilitados (modo con estado o sin estado) y perturbar permanentemente el manejo de tickets de sesión en esa escucha. Los nuevos ’handshakes’ de TLS 1.3 se completan pero posteriormente fallan cuando el servidor intenta emitir un ticket de sesión, haciendo que TLS 1.3 sea efectivamente inutilizable en la escucha afectada hasta que se reinicie la aplicación ssl. Las conexiones TLS 1.2 no se ven afectadas.\n\nEste problema afecta a OTP desde 22.2 antes de 29.0.3, 28.5.0.3 y 27.3.4.14 correspondiente a ssl desde 9.5 antes de 11.7.3, 11.6.0.3 y 11.2.12.10."
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          "modules": [
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          "programFiles": [
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          "programRoutines": [
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          "repo": "https://github.com/erlang/otp",
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          "modules": [
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          "programFiles": [
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          "programRoutines": [
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              "name": "tls_handshake_1_3:handle_pre_shared_key/3"
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          ],
          "repo": "https://github.com/erlang/otp",
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          "valueDensity": "NOT_DEFINED",
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    "cvssMetricV31": [
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}