CVE-2026-55215 is a high-severity (CVSS 7.5) CWE-295 vulnerability in mariadb. O3 Security confirms whether CVE-2026-55215 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
MariaDB's connector leaks the cleartext password to an MitM despite `ssl: true`
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
mariadbnpmDescription
Summary
When SSL/TLS is enabled but no CA / server certificate is provided, the connector verifies the server's identity using fingerprint validation. The check is effective, the connection is ultimately rejected when it fails, but it happens after the authentication exchange. As a result, the credentials are sent before validation occurs, so an active man-in-the-middle who presents their own certificate receives the password in the handshake before the connection is aborted.
Impact
The credentials are transmitted to the peer before the server's identity is validated. An on-path attacker (MitM) presenting any certificate can capture the account password, even though the connection then fails the fingerprint check and is closed. The disclosed credentials can subsequently be used to authenticate directly against the server.
- Attacker requirement: active man-in-the-middle position on the network path
- Affected configuration: SSL/TLS enabled without a CA / server certificate
Affected versions
- < 3.2.4
- 3.3.0 – 3.3.2
- 3.4.0 – 3.4.5
- 3.5.0 – 3.5.2
Patches
Fixed in 3.2.4, 3.3.3, 3.4.6, and 3.5.3. Upgrade to one of these (or later) on your branch.
Workarounds
Until you can upgrade, configure certificate verification explicitly, provide the server/CA certificate and use a verifying SSL mode (e.g. VERIFY_CA / VERIFY_FULL).
Reported by haaahaaahiihiiii (no GitHub account).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | mariadb | all versions | 3.2.4 |
| 📦npm | mariadb | ≥ 3.3.0&&< 3.3.3 | 3.3.3 |
| 📦npm | mariadb | ≥ 3.4.0&&< 3.4.6 | 3.4.6 |
| 📦npm | mariadb | ≥ 3.5.0&&< 3.5.3 | 3.5.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mariadb. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update mariadb to 3.2.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55215 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-55215 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-55215. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-55215 in your dependencies?
O3 detects CVE-2026-55215 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.