Improper Validation of Specified Quantity in Input in otp - CVE-2026-55952

 

Improper Validation of Specified Quantity in Input in otp - CVE-2026-55952

Published: July 2, 2026


Vulnerability identifier: #VU136823
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-55952
CWE-ID: CWE-1284
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper validation of specified quantity in input in the TLS-1.3 session ticket handler when processing a malformed ClientHello with mismatched PSK identity and binder list lengths. A remote attacker can send a specially crafted ClientHello message to cause a denial of service.

Only TLS-1.3 servers with session tickets enabled are vulnerable. TLS-1.2 connections are not affected.


Affected software

otp
openEuler
Fedora
erlang-compiler
erlang-reltool
erlang-public_key
erlang-parsetools
erlang-os_mon
erlang-odbc
erlang-observer
erlang-mnesia
erlang-megaco
erlang-kernel
erlang-jinterface
erlang-inets
erlang-hipe
erlang
erlang-asn1
erlang-common_test
erlang-runtime_tools
erlang-crypto
erlang-debugger
erlang-debuginfo
erlang-debugsource
erlang-dialyzer
erlang-diameter
erlang-edoc
erlang-eldap
erlang-erl_docgen
erlang-erl_interface
erlang-erts
erlang-et
erlang-eunit
erlang-examples
erlang-ftp
erlang-sasl
erlang-xmerl
erlang-wx
erlang-tools
erlang-tftp
erlang-syntax_tools
erlang-stdlib
erlang-ssl
erlang-ssh
erlang-snmp
erlang-src

How to mitigate CVE-2026-55952

Install security update from vendor's website.

otp - addressed in versions 27.3.4.14, 28.5.0.3, 29.0.3
erlang-compiler - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-reltool - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-public_key - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-parsetools - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-os_mon - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-odbc - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-observer - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-mnesia - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-megaco - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-kernel - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-jinterface - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-inets - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-hipe - update to 23.3.4.9-11
erlang - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-asn1 - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-common_test - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-runtime_tools - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-crypto - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-debugger - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-debuginfo - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-debugsource - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-dialyzer - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-diameter - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-edoc - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-eldap - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-erl_docgen - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-erl_interface - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-erts - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-et - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-eunit - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-examples - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-ftp - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-sasl - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-xmerl - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-wx - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-tools - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-tftp - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-syntax_tools - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-stdlib - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-ssl - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-ssh - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-snmp - addressed in versions 23.3.4.9-11, 25.3.2.6-18
erlang-src - update to 25.3.2.6-18
erlang - addressed in versions 26.2.5.21-4.fc43, 26.2.5.21-4.fc44

External References

Related Security Bulletins