CVE-2026-54891
LowCVSS 3.7Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
A vulnerability in the Erlang/OTP SSL library (tls_gen_connection module) involves improper enforcement of message integrity during transmission. A network attacker can inject unauthenticated plaintext to a TLS client during the handshake, which is later treated as authenticated server data by the application after the handshake completes.
Risk Assessment
The organization is at risk of blind injection of unauthenticated data into the TLS stream, potentially compromising communication integrity and allowing the application to process fake data as trusted.
Recommendation
Immediately upgrade Erlang/OTP to version 27.3.4.14, 28.5.0.3, or 29.0.3 (depending on the branch) and the corresponding ssl library to version 11.2.12.10, 11.6.0.3, or 11.7.3.
Original NVD description (English source)
Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Erlang/OTP ssl (tls_gen_connection module) allows a network-positioned attacker to inject unauthenticated plaintext that the TLS client application later treats as authenticated server data. The function tls_gen_connection:handle_protocol_record/3 rejects APPLICATION_DATA records that arrive in pre-handshake states when the TLS endpoint acts as a server, but does not apply the same check when the endpoint acts as a client. A network-positioned attacker can send plaintext APPLICATION_DATA records to the client during the handshake. The records are buffered and, once the handshake completes successfully, delivered to the application as if they were authenticated post-handshake data. The attacker cannot observe the client's response or steer the connection, so the impact is limited to blind injection of unauthenticated bytes. The injection window is wider for TLS versions prior to TLS 1.3 than for TLS 1.3. This vulnerability is associated with program file lib/ssl/src/tls_gen_connection.erl. TLS 1.3 is affected starting with OTP 22.0, when TLS 1.3 support was added. This issue affects OTP from OTP R13B03 before OTP 27.3.4.14, from OTP 28.0 before OTP 28.5.0.3, and from OTP 29.0 before OTP 29.0.3, corresponding to ssl from 3.10.7 before 11.2.12.10, from 11.3 before 11.6.0.3, and from 11.7 before 11.7.3. Whether OTP before OTP R13B03, corresponding to ssl before 3.10.7, is affected is unknown.