Vulnerability in dovecot (DEBIAN-CVE-2021-29157)

Summary

Vulnerability in dovecot (DEBIAN-CVE-2021-29157). Confidential information can be exposed externally. Mitigation: upgrade to 1:2.3.13+dfsg1-2 or later.

Original description

The description as published by the source.

Dovecot before 2.3.15 allows ../ Path Traversal. An attacker with access to the local filesystem can trick OAuth2 authentication into using an HS256 validation key from an attacker-controlled location. This occurs during use of local JWT validation with the posix fs driver.

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 DEBIAN-CVE-2021-29157 has been found in dovecot.
Confidential information can be exposed externally.
What to do: upgrade dovecot to 1:2.3.13+dfsg1-2 or later.
If unsure, ask your IT team or search "dovecot DEBIAN-CVE-2021-29157" on the vendor's site.

DEBIAN-CVE-2021-29157 (dovecot)
Attack vector: local / no user interaction
Patched: 1:2.3.13+dfsg1-2 — 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 dovecot.

📍 Affected scope

Check the vendor advisory for the affected versions of dovecot.

🔥 Severity

Severity: ?. Confidential information can be exposed externally.

🔧 How to fix

Update to 1:2.3.13+dfsg1-2.

🛡️ 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 'dovecot' . 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 'dovecot' . | 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 dovecot 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 dovecot to 1:2.3.13+dfsg1-2
```
ステージング環境で 1:2.3.13+dfsg1-2 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

Debian:12 dovecot

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.3.13+dfsg1-2"}]}]

Debian:13 dovecot

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.3.13+dfsg1-2"}]}]

Debian:14 dovecot

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.3.13+dfsg1-2"}]}]

References

advisory security-tracker.debian.org