SSRF (Server-Side Request Forgery) in Adminer (CVE-2026-100698)
Summary
SSRF in Adminer (CVE-2026-100698). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 5.5.0 or later.
Original description
The description as published by the source.
Adminer 5.5.1 through 6.0.1 improperly parses the login 'server' string in the host_port() function in adminer/include/functions.inc.php. The port capture group requires pure digits anchored to the end of the string, so any server value with a non-digit tail fails the regex and falls back to returning the whole string as the host with an empty port. Because the privileged-port restriction in adminer/include/auth.inc.php inspects only the parsed port, the check is skipped, and the mysqli/mysqlnd client subsequently re-parses host:port from the host string and opens a TCP connection. A remote, unauthenticated attacker who can reach the Adminer login page can submit a crafted value such as 127.0.0.1:80/x to make the server initiate TCP connections to arbitrary internal hosts and privileged ports before credentials are validated, enabling server-side request forgery and blind internal port scanning (connection refused vs. handshake vs. timeout acts as a liveness oracle). This is a regression that re-opens the bypass fixed in 5.5.0 (GHSA-58cq-mgw2-38m5). Fixed in 6.0.2.
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-100698 has been found in Adminer.
Risk of unauthorized operations or information disclosure. CVSS score: 5.8/10.
What to do: upgrade Adminer to 5.5.0 or later.
If unsure, ask your IT team or search "Adminer CVE-2026-100698" on the vendor's site.
CVE-2026-100698 (Adminer) — CWE-918 / CVSS v3 5.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 5.5.0 — 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.
SSRF (CWE-918) exists in Adminer.
Check the vendor advisory for the affected versions of Adminer.
Severity: Medium (CVSS 5.8/10). Risk of unauthorized operations or information disclosure.
Update to 5.5.0.
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 'Adminer' . 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 'Adminer' . | 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
Adminer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 Adminer to 5.5.0ステージング環境で 5.5.0 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。
-
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。
References
- web github.com
- web vulncheck.com
- web nvd.nist.gov
- web github.com