Vulnerability in redis (ALPINE-CVE-2021-32762)

Summary

Vulnerability in redis (ALPINE-CVE-2021-32762). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 5.0.14-r0 or later.

Original description

The description as published by the source.

Redis is an open source, in-memory database that persists on disk. The redis-cli command line tool and redis-sentinel service may be vulnerable to integer overflow when parsing specially crafted large multi-bulk network replies. This is a result of a vulnerability in the underlying hiredis library which does not perform an overflow check before calling the calloc() heap allocation function. This issue only impacts systems with heap allocators that do not perform their own overflow checks. Most modern systems do and are therefore not likely to be affected. Furthermore, by default redis-sentinel uses the jemalloc allocator which is also not vulnerable. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14.

Source: OSV.dev (Open Source Vulnerabilities) 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 ALPINE-CVE-2021-32762 has been found in redis.
Successful exploitation can lead to full system takeover.
What to do: upgrade redis to 5.0.14-r0 or later.
If unsure, ask your IT team or search "redis ALPINE-CVE-2021-32762" on the vendor's site.

ALPINE-CVE-2021-32762 (redis)
Attack vector: remote (network-reachable) / no user interaction
Patched: 5.0.14-r0 — 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.

❓ What is the problem

A vulnerability (unclassified) exists in redis.

📍 Affected scope

Check the vendor advisory for the affected versions of redis.

🔥 Severity

Severity: ?. Successful exploitation can lead to full system takeover.

🔧 How to fix

Update to 5.0.14-r0.

🛡️ 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 'redis' . 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 'redis' . | 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 redis を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade redis to 5.0.14-r0
```
ステージング環境で 5.0.14-r0 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。
3
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

Alpine:v3.11 redis

[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"5.0.14-r0"}]}]

Alpine:v3.12 redis

[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"5.0.14-r0"}]}]

Alpine:v3.13 redis

[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"6.0.16-r0"}]}]

Alpine:v3.14 redis