Vulnerability in otp (CVE-2026-21620)
Summary
Vulnerability in otp (CVE-2026-21620). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
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 17.0, from 07b8f441ca711f9812fad9e9115bab3c3aa92f79; otp: from 5.10 before 7.0; otp: from 1.0.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-21620 has been found in otp.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "otp CVE-2026-21620" on the vendor's site.
CVE-2026-21620 (otp) — CWE-23
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-23) exists in otp.
Check the vendor advisory for the affected versions of otp.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'otp' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'otp' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
otpを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-21620 erlang Fixed in: 1:23.2.6+dfsg-1+deb11u4
- Ubuntu UBUNTU-CVE-2026-21620 erlang Fixed in: 1:16.b.3-dfsg-1ubuntu2.2+esm3
References
- web erlang.org
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web cna.erlef.org
- web osv.dev