CVE-2026-21620
TFTP Path Traversal
Relative Path Traversal, Improper Isolation or Compartmentalization vulnerability in erlang otp erlang/otp (tftp_file modules), erlang otp inets (tftp_file modules), erlang otp tftp (tftp_file modules) allows Relative Path Traversal. This vulnerability is associated with program files lib/tftp/src/tftp_file.erl, src/tftp_file.erl. This issue affects OTP from OTP 17.0 before OTP 26.2.5.17, OTP 27.3.4.8, and OTP 28.3.2, corresponding to inets from 5.10 before 7.0, and tftp from 1.0 before 1.1.1.1, 1.2.2.1, and 1.2.4.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: EEFFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: EEFFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: EEFFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: EEFAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| OTP Erlang otp
software-id |
≥ 17.0; < * (affected, otp); unaffected at 26.2.5.17; unaffected at 27.3.4.8; unaffected at 28.3.2
Other versions: unaffected |
CNA: EEF |
| OTP Erlang inets
otp |
≥ 5.10; < 7.0 (affected, otp)
Other versions: unaffected |
CNA: EEF |
| OTP Erlang tftp
otp |
≥ 1.0; < * (affected, otp); unaffected at 1.1.1.1; unaffected at 1.2.2.1; unaffected at 1.2.4
Other versions: unaffected |
CNA: EEF |
| OTP Erlang erlang/otp
github |
≥ 07b8f441ca711f9812fad9e9115bab3c3aa92f79; < * (affected, git); unaffected at 655fb95725ba2fb811740b57e106873833824344; unaffected at 3970738f687325138eb75f798054fa8960ac354e; unaffected at 696fdec922661d4a3cc528fc34bc24fae8d4ad8a
Other versions: unaffected |
CNA: EEF |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 2.3 low |
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N | CNA: EEF |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/erlang/otp/security/advisories/GHSA-hmrc-prh3-rpvpCNA: EEF · vendor-advisory, related
- https://cna.erlef.org/cves/CVE-2026-21620.htmlCNA: EEF · related
- https://osv.dev/vulnerability/EEF-CVE-2026-21620CNA: EEF · related
- https://www.erlang.org/doc/system/versions.html#order-of-versionsCNA: EEF · x_version-scheme
- https://github.com/erlang/otp/pull/10706CNA: EEF · patch
- https://github.com/erlang/otp/commit/07b8f441ca711f9812fad9e9115bab3c3aa92f79CNA: EEF · related
- https://github.com/erlang/otp/commit/655fb95725ba2fb811740b57e106873833824344CNA: EEF · patch
- https://github.com/erlang/otp/commit/3970738f687325138eb75f798054fa8960ac354eCNA: EEF · patch
- https://github.com/erlang/otp/commit/696fdec922661d4a3cc528fc34bc24fae8d4ad8aCNA: EEF · patch
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