CVE-2026-23942: Erlang OTP · Path Traversal
Affects Erlang OTPSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium : upgrade to 5.5.1 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.5.1, 28.4.1
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 13 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade OTP and erlang/otp and ssh to 5.5.1; OTP and erlang/otp to 28.4.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ErlangOTP | Affected
| Fixed in
|
| ErlangOTP | Affected
| Fixed in
|
GitHuberlang/otppkg:github/erlang/otpOther threats | Affected
| Fixed in
|
GitHubsshpkg:github/sshOther threats | Affected
| Fixed in
|
GitHuberlang/otppkg:github/erlang/otpOther threats | Affected
| Fixed in
|
CPE configurations (1)
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, restrict access to the SFTP server to trusted users only and monitor for unusual access patterns related to directory traversal attempts.
Description
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 before OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to ssh from 3.0.1 before 5.5.1, 5.2.11.6 and 5.1.4.14.
References
- github.com/erlang/otp/security/advisories/GHSA-4749-w85x-hw9h (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-23942.html (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-23942 (opens in a new tab)
- erlang.org/doc/system/versions.html (opens in a new tab)
- github.com/erlang/otp/commit/27688a824f753d4c16371dc70e88753fb410590b (opens in a new tab)
- github.com/erlang/otp/commit/9e0ac85d3485e7898e0da88a14be0ee2310a3b28 (opens in a new tab)
- github.com/erlang/otp/commit/5ed603a1211b83b8be2d1fc06d3f3bf30c3c9759 (opens in a new tab)