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.
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--- inets-9.1.0.5 ---------------------------------------------------
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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
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--- ssh-5.1.4.14 ----------------------------------------------------
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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
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--- ssl-11.1.4.12 ---------------------------------------------------
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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
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--- Thanks to -------------------------------------------------------
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Hewwho
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