Improper handling of highly compressed data in otp - CVE-2026-23943
Published: April 10, 2026
Vulnerability identifier: #VU125773
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-23943
CWE-ID: CWE-409
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: erlang
Affected software:
otp
otp
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper handling of highly compressed data in ssh compression handling when decompressing crafted compressed packets. A remote attacker can send compressed packets that expand to excessive sizes when decompressed to cause a denial of service.
The zlib algorithm enables unauthenticated attacks after key exchange, while zlib@openssh.com enables attacks after authentication. When parallel_login=true, memory consumption can reach multiple gigabytes.
How to mitigate CVE-2026-23943
Install security update from vendor's website.