CVE-2026-55952

Published Jul 2, 2026

Last updated 15 days ago

CVSS high 8.2
SSL

Overview

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 22.2 before 29.0.3, 28.5.0.3 and 27.3.4.14 corresponding to ssl from 9.5 before 11.7.3, 11.6.0.3 and 11.2.12.10.
Source
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
NVD status
Analyzed
Products
erlang\/otp, erlang\/ssl

Risk scores

CVSS 4.0

Type
Secondary
Base score
8.2
Impact score
-
Exploitability score
-
Vector string
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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
Severity
HIGH

CVSS 3.1

Type
Primary
Base score
7.5
Impact score
3.6
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity
HIGH

Weaknesses

6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CWE-1284

Social media

Hype score
Not currently trending

  1. ⚠️ Vulnerabilidades en productos Erlang ❗ CVE-2026-55952 ❗ CVE-2026-55950 ➡️ Más info: https://t.co/MOFgkafWJj https://t.co/NwBqjKLwTn

    @CERTpy

    17 Jul 2026

    173 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.