CVE-2026-23943 Improper Handling of Highly Compressed Data (Compression Bomb) vulnerability in Erlang OTP ssh (ssh_transport modules)…
Description
Improper Handling of Highly Compressed Data (Compression Bomb) vulnerability in Erlang OTP ssh (ssh_transport modules) allows Denial of Service via Resource Depletion. The SSH transport layer advertises legacy zlib compression by default and inflates attacker-controlled payloads pre-authentication without any size limit, enabling reliable memory exhaustion DoS. Two compression algorithms are affected: * zlib: Activates immediately after key exchange, enabling unauthenticated attacks * zlib@openssh.com: Activates post-authentication, enabling authenticated attacks Each SSH packet can decompress ~255 MB from 256 KB of wire data (1029:1 amplification ratio). Multiple packets can rapidly exhaust available memory, causing OOM kills in memory-constrained environments. This vulnerability is associated with program files lib/ssh/src/ssh_transport.erl and program routines ssh_transport:decompress/2, ssh_transport:handle_packet_part/4. This issue affects OTP from OTP 17.0 before OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to ssh from 3.0.1 before 5.5.1, 5.2.11.6 and 5.1.4.14.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| otp 17.0 | 17.0 → latest | No fix stated |
References
- github.com github.com
- cna.erlef.org cna.erlef.org
- osv.dev osv.dev
- www.erlang.org www.erlang.org
- github.com github.com
- github.com github.com
- github.com github.com
Timeline
- Published
- Last modified