Patch Package:           OTP 26.2.5.18
Git Tag:                 OTP-26.2.5.18
Date:                    2026-03-12
Trouble Report Id:       OTP-19795, OTP-20007, OTP-20009, OTP-20011,
                         OTP-20022
Seq num:                 CVE-2026-23941, CVE-2026-23942,
                         CVE-2026-23943, ERIERL-1305, GH-10694,
                         PR-10465, PR-10707, PR-10811, PR-10813,
                         PR-10833
System:                  OTP
Release:                 26
Application:             inets-9.1.0.5, ssh-5.1.4.14, ssl-11.1.4.12
Predecessor:             OTP 26.2.5.17

 Check out the git tag OTP-26.2.5.18, and build a full OTP system
 including documentation. Apply one or more applications from this
 build as patches to your installation using the 'otp_patch_apply'
 tool. For information on install requirements, see descriptions for
 each application version below.

 ---------------------------------------------------------------------
 --- inets-9.1.0.5 ---------------------------------------------------
 ---------------------------------------------------------------------

 The inets-9.1.0.5 application can be applied independently of other
 applications on a full OTP 26 installation.

 --- Fixed Bugs and Malfunctions ---

  OTP-20007    Application(s): inets
               Related Id(s): PR-10833, CVE-2026-23941

               The httpd server now rejects HTTP requests containing
               multiple Content-Length headers with different values,
               returning a 400 Bad Request response. This prevents
               potential HTTP request smuggling attacks. Thanks
               Luigino Camastra at Aisle Research for responsibly
               disclosing this vulnerability


 Full runtime dependencies of inets-9.1.0.5: erts-14.0, kernel-9.0,
 mnesia-4.12, public_key-1.13, runtime_tools-1.8.14, ssl-9.0,
 stdlib-5.0, stdlib-5.0


 ---------------------------------------------------------------------
 --- ssh-5.1.4.14 ----------------------------------------------------
 ---------------------------------------------------------------------

 The ssh-5.1.4.14 application can be applied independently of other
 applications on a full OTP 26 installation.

 --- Fixed Bugs and Malfunctions ---

  OTP-20009    Application(s): ssh
               Related Id(s): PR-10811, CVE-2026-23942

               Fixed path traversal vulnerability in SFTP server's
               root option allowing authenticated users to access
               sibling directories with matching name prefixes. The
               root option used string prefix matching instead of path
               component validation. With {root, "/home/user1"},
               attackers could access /home/user10/ or /home/user123/.
               Thanks to Luigino Camastra, Aisle Research.


  OTP-20011    Application(s): ssh
               Related Id(s): PR-10813, CVE-2026-23943

               Fixed excessive memory usage vulnerability in SSH
               compression allowing attackers to consume system
               resources through decompression bombs. The 'zlib' and
               'zlib@openssh.com' algorithms lacked decompression size
               limits, allowing 256 KB packets to expand to 255 MB
               (1029:1 ratio). This could lead to crashes on systems
               with limited memory.

               The fix removes zlib from default compression
               algorithms and implements decompression size limits for
               both algorithms. Thanks to Igor Morgenstern at Aisle
               Research


 Full runtime dependencies of ssh-5.1.4.14: crypto-5.0, erts-14.0,
 kernel-9.0, public_key-1.6.1, runtime_tools-1.15.1, stdlib-5.0,
 stdlib-5.0


 ---------------------------------------------------------------------
 --- ssl-11.1.4.12 ---------------------------------------------------
 ---------------------------------------------------------------------

 The ssl-11.1.4.12 application can be applied independently of other
 applications on a full OTP 26 installation.

 --- Fixed Bugs and Malfunctions ---

  OTP-19795    Application(s): ssl
               Related Id(s): PR-10465

               Correct TLS-1.3 alert handling so server will always
               send the alert with the encryption keys that the client
               is expecting, that is if for instance if client
               certification fails the alert will be sent using
               application traffic encryption keys.


  OTP-20022    Application(s): ssl
               Related Id(s): ERIERL-1305, GH-10694, PR-10707

               TLS-1.3 certificate request now preserves the order of
               signature algorithms in certificate request extension
               to be in the servers preferred order, which might
               affect the choice made by some TLS clients.


 Full runtime dependencies of ssl-11.1.4.12: crypto-5.0, erts-14.0,
 inets-5.10.7, kernel-9.0, public_key-1.11.3, runtime_tools-1.15.1,
 stdlib-4.1


 ---------------------------------------------------------------------
 --- Thanks to -------------------------------------------------------
 ---------------------------------------------------------------------

 Hewwho


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