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6 vulnerabilities found for erlang\/ssh by erlang

CVE-2026-32147 (GCVE-0-2026-32147)

Vulnerability from nvd – Published: 2026-04-21 12:01 – Updated: 2026-04-22 04:13
VLAI
Title
SFTP chroot bypass via path traversal in SSH_FXP_FSETSTAT
Summary
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP ssh (ssh_sftpd module) allows an authenticated SFTP user to modify file attributes outside the configured chroot directory. The SFTP daemon (ssh_sftpd) stores the raw, user-supplied path in file handles instead of the chroot-resolved path. When SSH_FXP_FSETSTAT is issued on such a handle, file attributes (permissions, ownership, timestamps) are modified on the real filesystem path, bypassing the root directory boundary entirely. Any authenticated SFTP user on a server configured with the root option can modify file attributes of files outside the intended chroot boundary. The prerequisite is that a target file must exist on the real filesystem at the same relative path. Note that this vulnerability only allows modification of file attributes; file contents cannot be read or altered through this attack vector. If the SSH daemon runs as root, this enables direct privilege escalation: an attacker can set the setuid bit on any binary, change ownership of sensitive files, or make system configuration world-writable. This vulnerability is associated with program files lib/ssh/src/ssh_sftpd.erl and program routines ssh_sftpd:do_open/4 and ssh_sftpd:handle_op/4. This issue affects OTP from OTP 17.0 until OTP 28.4.3, 27.3.4.11, and 26.2.5.20 corresponding to ssh from 3.01 until 5.5.3, 5.2.11.7, and 5.1.4.15.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.01 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 07b8f441ca711f9812fad9e9115bab3c3aa92f79 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
John Downey Michał Wąsowski Jakub Witczak
Show details on NVD website
To clipboard 

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CVE-2026-23943 (GCVE-0-2026-23943)

Vulnerability from nvd – Published: 2026-03-13 09:11 – Updated: 2026-05-27 15:41
VLAI
Title
Pre-auth SSH DoS via unbounded zlib inflate
Summary
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 until OTP 28.4.1, 27.3.4.9 and 26.2.5.18 corresponding to ssh from 3.0.1 until 5.5.1, 5.2.11.6 and 5.1.4.14.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.0.1 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 07b8f441ca711f9812fad9e9115bab3c3aa92f79 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Igor Morgenstern / Aisle Research Michał Wąsowski Jakub Witczak
Show details on NVD website
To clipboard 

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CVE-2026-23942 (GCVE-0-2026-23942)

Vulnerability from nvd – Published: 2026-03-13 09:11 – Updated: 2026-05-27 15:41
VLAI
Title
SFTP root escape via component-agnostic prefix check in ssh_sftpd
Summary
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP (ssh_sftpd module) allows Path Traversal. This vulnerability is associated with program files lib/ssh/src/ssh_sftpd.erl and program routines ssh_sftpd:is_within_root/2. The SFTP server uses string prefix matching via lists:prefix/2 rather than proper path component validation when checking if a path is within the configured root directory. This allows authenticated users to access sibling directories that share a common name prefix with the configured root directory. For example, if root is set to /home/user1, paths like /home/user10 or /home/user1_backup would incorrectly be considered within the root. This issue affects OTP from OTP 17.0 until OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to ssh from 3.0.1 until 5.5.1, 5.2.11.6 and 5.1.4.14.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.0.1 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 0 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Luigino Camastra / Aisle Research Jakub Witczak Michał Wąsowski
Show details on NVD website
To clipboard 

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CVE-2026-32147 (GCVE-0-2026-32147)

Vulnerability from cvelistv5 – Published: 2026-04-21 12:01 – Updated: 2026-04-22 04:13
VLAI
Title
SFTP chroot bypass via path traversal in SSH_FXP_FSETSTAT
Summary
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP ssh (ssh_sftpd module) allows an authenticated SFTP user to modify file attributes outside the configured chroot directory. The SFTP daemon (ssh_sftpd) stores the raw, user-supplied path in file handles instead of the chroot-resolved path. When SSH_FXP_FSETSTAT is issued on such a handle, file attributes (permissions, ownership, timestamps) are modified on the real filesystem path, bypassing the root directory boundary entirely. Any authenticated SFTP user on a server configured with the root option can modify file attributes of files outside the intended chroot boundary. The prerequisite is that a target file must exist on the real filesystem at the same relative path. Note that this vulnerability only allows modification of file attributes; file contents cannot be read or altered through this attack vector. If the SSH daemon runs as root, this enables direct privilege escalation: an attacker can set the setuid bit on any binary, change ownership of sensitive files, or make system configuration world-writable. This vulnerability is associated with program files lib/ssh/src/ssh_sftpd.erl and program routines ssh_sftpd:do_open/4 and ssh_sftpd:handle_op/4. This issue affects OTP from OTP 17.0 until OTP 28.4.3, 27.3.4.11, and 26.2.5.20 corresponding to ssh from 3.01 until 5.5.3, 5.2.11.7, and 5.1.4.15.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.01 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 07b8f441ca711f9812fad9e9115bab3c3aa92f79 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
John Downey Michał Wąsowski Jakub Witczak
Show details on NVD website
To clipboard 

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CVE-2026-23943 (GCVE-0-2026-23943)

Vulnerability from cvelistv5 – Published: 2026-03-13 09:11 – Updated: 2026-05-27 15:41
VLAI
Title
Pre-auth SSH DoS via unbounded zlib inflate
Summary
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 until OTP 28.4.1, 27.3.4.9 and 26.2.5.18 corresponding to ssh from 3.0.1 until 5.5.1, 5.2.11.6 and 5.1.4.14.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.0.1 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 07b8f441ca711f9812fad9e9115bab3c3aa92f79 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Igor Morgenstern / Aisle Research Michał Wąsowski Jakub Witczak
Show details on NVD website
To clipboard 

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CVE-2026-23942 (GCVE-0-2026-23942)

Vulnerability from cvelistv5 – Published: 2026-03-13 09:11 – Updated: 2026-05-27 15:41
VLAI
Title
SFTP root escape via component-agnostic prefix check in ssh_sftpd
Summary
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP (ssh_sftpd module) allows Path Traversal. This vulnerability is associated with program files lib/ssh/src/ssh_sftpd.erl and program routines ssh_sftpd:is_within_root/2. The SFTP server uses string prefix matching via lists:prefix/2 rather than proper path component validation when checking if a path is within the configured root directory. This allows authenticated users to access sibling directories that share a common name prefix with the configured root directory. For example, if root is set to /home/user1, paths like /home/user10 or /home/user1_backup would incorrectly be considered within the root. This issue affects OTP from OTP 17.0 until OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to ssh from 3.0.1 until 5.5.1, 5.2.11.6 and 5.1.4.14.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
EEF
References
Impacted products
Vendor Product Version
Erlang OTP Affected: 3.0.1 , < * (otp)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Erlang OTP Affected: 17.0 , < * (otp)
Affected: 0 , < * (git)
    cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Luigino Camastra / Aisle Research Jakub Witczak Michał Wąsowski
Show details on NVD website
To clipboard 

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    "dateUpdated": "2026-05-27T15:41:40.808Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}