Vulnerability in samba (UBUNTU-CVE-2026-58222)
Summary
Vulnerability in samba (UBUNTU-CVE-2026-58222). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 2:4.15.13+dfsg-0ubuntu1.13 or later.
Original description
The description as published by the source.
A security flaw combining LDAP filter injection and improper authorization checks was found in Samba Active Directory Domain Controller (AD DC). When processing LDAP Compare requests, Samba fails to properly validate user-supplied attribute names and executes the resulting internal database search in a trusted context, bypassing normal Access Control List (ACL) enforcement. An authenticated low-privilege domain user can exploit these flaws to disclose confidential Active Directory attributes that would normally be inaccessible. The disclosed information may be leveraged to derive sensitive authentication material, potentially leading to privilege escalation and complete domain compromise. For example: In deployments configured with Group Managed Service Accounts (gMSAs), an attacker can extract the "msKds-RootKeyData" attribute and derive gMSA passwords offline, potentially leading to complete domain compromise if privileged gMSAs are present.
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 UBUNTU-CVE-2026-58222 has been found in samba.
Successful exploitation can lead to full system takeover.
What to do: upgrade samba to 2:4.15.13+dfsg-0ubuntu1.13 or later.
If unsure, ask your IT team or search "samba UBUNTU-CVE-2026-58222" on the vendor's site.
UBUNTU-CVE-2026-58222 (samba)
Attack vector: remote (network-reachable) / no user interaction
Patched: 2:4.15.13+dfsg-0ubuntu1.13 — 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.
A vulnerability (unclassified) exists in samba.
Check the vendor advisory for the affected versions of samba.
Severity: ?. Successful exploitation can lead to full system takeover.
Update to 2:4.15.13+dfsg-0ubuntu1.13.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'samba' . 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
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1Identify exposure identify
grep -r 'samba' . | 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
sambaを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade samba to 2:4.15.13+dfsg-0ubuntu1.13ステージング環境で 2:4.15.13+dfsg-0ubuntu1.13 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。
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3Post-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
References
- advisory ubuntu.com
- report ubuntu.com
- report cve.org