CVE-2026-23942
published 2026-03-13CVE-2026-23942: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP (ssh_sftpd module) allows Path Traversal. This…
PriorityP335medium5.4CVSS 3.1
AVNACLPRLUINSUCLILAN
EPSS
0.36%
28.1th percentile
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.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | erlang | < erlang 1:27.3.4.9+dfsg-1 (forky) | erlang 1:27.3.4.9+dfsg-1 (forky) |
| erlang | erlang_otp | >= 17.0 < 26.2.5.18 | 26.2.5.18 |
| erlang | erlang_otp | >= 27.0 < 27.3.4.9 | 27.3.4.9 |
| erlang | erlang_otp | >= 28.0 < 28.4.1 | 28.4.1 |
| erlang | erlang_ssh | >= 3.0.1 < 5.1.4.14 | 5.1.4.14 |
| erlang | erlang_ssh | >= 5.2 < 5.2.11.6 | 5.2.11.6 |
| erlang | erlang_ssh | 5.5 – 5.5.1 | — |
| erlang | otp | < * | * |
| erlang | otp | >= 17.0 < * | * |
| erlang | otp | >= 3.0.1 < * | * |
| msrc | azl3_erlang_26.2.5.17-1_on_azure_linux_3.0 | — | — |
| msrc | cbl2_erlang_25.3.2.21-4_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
nvdv4.05.3MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv5.3MEDIUM
vendor_debian5.3MEDIUM
vendor_msrc5.3MEDIUM
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OSV
CVE-2026-23942: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP (ssh_sftpd module) allows Path Traversal
osv·2026-03-13·CVSS 5.3
CVE-2026-23942 [MEDIUM] CVE-2026-23942: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Erlang OTP (ssh_sftpd module) allows Path Traversal
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
Microsoft
SFTP root escape via component-agnostic prefix check in ssh_sftpd
vendor_msrc·2026-03-10·CVSS 5.3
CVE-2026-23942 [MEDIUM] CWE-22 SFTP root escape via component-agnostic prefix check in ssh_sftpd
SFTP root escape via component-agnostic prefix check in ssh_sftpd
Mariner: Mariner
EEF: EEF
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade
Debian
CVE-2026-23942: erlang - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') v...
vendor_debian·2026·CVSS 5.3
CVE-2026-23942 [MEDIUM] CVE-2026-23942: erlang - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') v...
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
No detection rules found.
No public exploits indexed.
https://cna.erlef.org/cves/CVE-2026-23942.htmlhttps://github.com/erlang/otp/commit/27688a824f753d4c16371dc70e88753fb410590bhttps://github.com/erlang/otp/commit/5ed603a1211b83b8be2d1fc06d3f3bf30c3c9759https://github.com/erlang/otp/commit/9e0ac85d3485e7898e0da88a14be0ee2310a3b28https://github.com/erlang/otp/security/advisories/GHSA-4749-w85x-hw9hhttps://osv.dev/vulnerability/EEF-CVE-2026-23942https://www.erlang.org/doc/system/versions.html#order-of-versions
2026-03-13
Published