Vulnerability in shrine (CVE-2020-15237)
Summary
Vulnerability in shrine (CVE-2020-15237). Confidential information can be exposed externally. Exploitable via derivation_endpoint. Mitigation: upgrade to 3.3.0 or later.
Original description
The description as published by the source.
Impact
When using the derivation_endpoint plugin, it's possible for the attacker to use a timing attack to guess the signature of the derivation URL.
Patches
The problem has been fixed by comparing sent and calculated signature in constant time, using Rack::Utils.secure_compare. Users using the derivation_endpoint plugin are urged to upgrade to Shrine 3.3.0 or greater.
Workarounds
Users of older Shrine versions can apply the following monkey-patch after loading the derivation_endpoint plugin:
class Shrine
class UrlSigner
def verify_signature(string, signature)
if signature.nil?
fail InvalidSignature, "missing \"signature\" param"
elsif !Rack::Utils.secure_compare(signature, generate_signature(string))
fail InvalidSignature, "provided signature does not match the calculated signature"
end
end
end
end
References
You can read more about timing attacks here.
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-2020-15237 has been found in shrine.
Attackers can target a specific entry point like derivation_endpoint over the network to misuse the product.
Confidential information can be exposed externally.
What to do: upgrade shrine to 3.3.0 or later.
If unsure, ask your IT team or search "shrine CVE-2020-15237" on the vendor's site.
CVE-2020-15237 (shrine) — CWE-203
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: derivation_endpoint
Patched: 3.3.0 — 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.
A vulnerability (CWE-203) exists in shrine. Attackers reach the vulnerable code path via derivation_endpoint without authentication.
Check the vendor advisory for the affected versions of shrine. Attack surface: derivation_endpoint.
Severity: ?. Confidential information can be exposed externally.
Update to 3.3.0.
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 'shrine' . 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 'shrine' . | 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
shrine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 shrine to 3.3.0ステージング環境で 3.3.0 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
- web github.com
- web github.com
- web github.com