Vulnerability in Go (CVE-2021-33196)

Summary

Vulnerability in Go (CVE-2021-33196). Risk of unauthorized operations or information disclosure.

Original description

The description as published by the source.

In archive/zip in Go before 1.15.13 and 1.16.x before 1.16.5, a crafted file count (in an archive's header) can cause a NewReader or OpenReader panic.

Source: OSV.dev (Open Source Vulnerabilities) NVD 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-2021-33196 has been found in Go.
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 "Go CVE-2021-33196" on the vendor's site.

CVE-2021-33196 (Go)
Attack vector: remote (network-reachable) / unauthenticated / 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 (unclassified) exists in Go.

📍 Affected scope

Check the vendor advisory for the affected versions of Go.

🔥 Severity

Severity: ?. 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 'Go' . 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 'Go' . | 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 Go 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。

Affected packages

Bitnami golang

[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.15.13"},{"introduced":"1.16.0"},{"fixed":"1.16.5"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

Debian DEBIAN-CVE-2021-33196 golang-1.15 Fixed in: 1.15.9-4