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CVE-2026-54891

Plaintext APPLICATION_DATA injected during TLS handshake delivered to client application post-handshake in ssl

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 27.3.4.14, 28.5.0.3, 29.0.3, 11.2.12.10, 11.6.0.3, and 1 more
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: partial

Summary

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 17.0 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 5.3.4 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 17.0, corresponding to ssl before 5.3.4, is affected is unknown.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • otp

    From 17.0 · fixed in 27.3.4.14; From 28.0 · fixed in 28.5.0.3; From 29.0 · fixed in 29.0.3

  • ssl

    From 5.3.4 · fixed in 11.2.12.10; From 11.3 · fixed in 11.6.0.3; From 11.7 · fixed in 11.7.3

  • erlang/otp

    Version range not reported

References 5

GitHub · erlang/otp

cna.erlef.org

osv.dev

erlang.org