Path Traversal in github.com/valyala/fasthttp (CVE-2022-21221)
Summary
Path traversal in github.com/valyala/fasthttp (CVE-2022-21221). Confidential information can be exposed externally. Mitigation: upgrade to 1.34.0 or later.
Original description
The description as published by the source.
The fasthttp.FS request handler is vulnerable to directory traversal attacks on Windows systems, and can serve files from outside the provided root directory.
URL path normalization does not handle Windows path separators (backslashes), permitting an attacker to construct requests with relative paths.
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-2022-21221 has been found in github.com/valyala/fasthttp.
Confidential information can be exposed externally.
What to do: upgrade github.com/valyala/fasthttp to 1.34.0 or later.
If unsure, ask your IT team or search "github.com/valyala/fasthttp CVE-2022-21221" on the vendor's site.
CVE-2022-21221 (github.com/valyala/fasthttp) — CWE-22
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 1.34.0 — apply immediately
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.
Path traversal (CWE-22) exists in github.com/valyala/fasthttp.
Check the vendor advisory for the affected versions of github.com/valyala/fasthttp.
Severity: ?. Confidential information can be exposed externally.
Update to 1.34.0.
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 'github.com/valyala/fasthttp' . 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 'github.com/valyala/fasthttp' . | 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
github.com/valyala/fasthttpを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/valyala/fasthttp to 1.34.0ステージング環境で 1.34.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-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。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- patch github.com
- web github.com
- web github.com
- web github.com
- web pkg.go.dev
- web snyk.io