Vulnerability in Codeready Linux Builder (CVE-2021-3733, CVSS 6.5)

Summary

Vulnerability in Codeready Linux Builder (CVE-2021-3733). Risk of unauthorized operations or information disclosure.

Original description

The description as published by the source.

There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.

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-2021-3733 has been found in Codeready Linux Builder.
Risk of unauthorized operations or information disclosure. CVSS score: 6.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Codeready Linux Builder CVE-2021-3733" on the vendor's site.

CVE-2021-3733 (Codeready Linux Builder) — CWE-400 / CVSS v3 6.5
Attack vector: remote (network-reachable) / no user interaction
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

A vulnerability (CWE-400) exists in Codeready Linux Builder.

📍 Affected scope

Check the vendor advisory for the affected versions of Codeready Linux Builder.

🔥 Severity

Severity: Medium (CVSS 6.5/10). 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. Audit SBOM/dependencies to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
Audit SBOM/dependencies for affected components.
```
資産台帳・SBOM・依存マニフェストで Codeready Linux Builder を使っているサービスとバージョンを洗い出す。
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。

Affected packages

Bitnami python-min

[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.6.14"},{"introduced":"3.7.0"},{"fixed":"3.7.11"},{"introduced":"3.8.0"},{"fixed":"3.8.10"},{"introduced":"3.9.0"},{"fixed":"3.9.5"},{"introduced":"3.10.0"},{"fixed":"3.10.1"}]}]

Bitnami libpython

[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.6.14"},{"introduced":"3.7.0"},{"fixed":"3.7.11"},{"introduced":"3.8.0"},{"fixed":"3.8.10"},{"introduced":"3.9.0"},{"fixed":"3.9.5"}]}]

Bitnami python