Cross-Site Scripting (XSS) in Captcha (CVE-2017-2171, CVSS 6.1)

Summary

Cross-site scripting in Captcha (CVE-2017-2171). Risk of unauthorized operations or information disclosure.

Original description

The description as published by the source.

Cross-site scripting vulnerability in Captcha prior to version 4.3.0, Car Rental prior to version 1.0.5, Contact Form Multi prior to version 1.2.1, Contact Form prior to version 4.0.6, Contact Form to DB prior to version 1.5.7, Custom Admin Page prior to version 0.1.2, Custom Fields Search prior to version 1.3.2, Custom Search prior to version 1.36, Donate prior to version 2.1.1, Email Queue prior to version 1.1.2, Error Log Viewer prior to version 1.0.6, Facebook Button prior to version 2.54, Featured Posts prior to version 1.0.1, Gallery Categories prior to version 1.0.9, Gallery prior to version 4.5.0, Google +1 prior to version 1.3.4, Google AdSense prior to version 1.44, Google Analytics prior to version 1.7.1, Google Captcha (reCAPTCHA) prior to version 1.28, Google Maps prior to version 1.3.6, Google Shortlink prior to version 1.5.3, Google Sitemap prior to version 3.0.8, Htaccess prior to version 1.7.6, Job Board prior to version 1.1.3, Latest Posts prior to version 0.3, Limit Attempts prior to version 1.1.8, LinkedIn prior to version 1.0.5, Multilanguage prior to version 1.2.2, PDF & Print prior to version 1.9.4, Pagination prior to version 1.0.7, Pinterest prior to version 1.0.5, Popular Posts prior to version 1.0.5, Portfolio prior to version 2.4, Post to CSV prior to version 1.3.1, Profile Extra prior to version 1.0.7. PromoBar prior to version 1.1.1, Quotes and Tips prior to version 1.32, Re-attacher prior to version 1.0.9, Realty prior to version 1.1.0, Relevant…

Source: NIST National Vulnerability Database NVD

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-2017-2171 has been found in Captcha.
Risk of unauthorized operations or information disclosure. CVSS score: 6.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Captcha CVE-2017-2171" on the vendor's site.

CVE-2017-2171 (Captcha) — CWE-79 / CVSS v3 6.1
Attack vector: remote (network-reachable) / unauthenticated
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.

❓ What is the problem

Cross-site scripting (XSS) (CWE-79) exists in Captcha.

📍 Affected scope

Check the vendor advisory for the affected versions of Captcha.

🔥 Severity

Severity: Medium (CVSS 6.1/10). Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to the patched release per vendor advisory.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Captcha' . 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

1
Identify exposure identify
```
grep -r 'Captcha' . | 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 Captcha を grep し、稼働しているサービス・バージョンを把握する。
2
Post-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。

References

advisory jvndb.jvn.jp
advisory jvn.jp