CVE-2026-55856

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 87% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases. Prior to 2.7.14, 3.3.5, 3.4.3, and 3.5.9, when a Java application connects with sslMode=verify-full or sslMode=verify-ca, supplies a password, and does not configure serverSslCert or trustStore, Connector/J can accept an untrusted self-signed certificate through the fallbackToSystemTrustStore=true ephemeral trust manager and record its certFingerprint for later identity binding. The OK-packet and authentication-switch paths enforce the certificate fingerprint, but the initial-handshake path does not. HandshakeResponse.encode() can therefore build and send a mysql_clear_password response before checking certFingerprint != null && !isMitMProof(), sslMode, or whether the authentication plugin is resistant to a man-in-the-middle, and the initial path also bypasses restrictedAuth. An active man-in-the-middle or hostile server can present a self-signed certificate, claim to be MariaDB, select mysql_clear_password as the initial authentication plugin, and receive the full database password before the connection is rejected. This issue is fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9.

CVSS v3
5.9
EG Score
5.9(medium)
EG Risk
27(Track)
EG Risk 27/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity59% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

August 28, 2026

Last Modified

September 8, 2026

Advisory Details (6)

Auto-updated Aug 28, 2026
Patch available. Sources: github_commit, github_release, github.
generic

[CONJ-1325] initial-handshake cleartext password leak - Jira

https://jira.mariadb.org/browse/CONJ-1325
github_release Patch Available

MariaDB Connector/Java 3.5.9

Patch available: mariadb-corporation/mariadb-connector-j 3.5.9

https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.5.9
github_release Patch Available

MariaDB Connector/Java 3.4.3

Patch available: mariadb-corporation/mariadb-connector-j 3.4.3

https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.4.3
github_commit Patch Available

commit d90b9872322c (mariadb-corporation/mariadb-connector-j)

Patch available: mariadb-corporation/mariadb-connector-j 3.5.9 (contains commit d90b9872322c)

https://github.com/mariadb-corporation/mariadb-connector-j/commit/d90b9872322c76b05a48219be66bff1d33102f8a
github_commit Patch Available

commit 149ec6a62637 (mariadb-corporation/mariadb-connector-j)

Patch available: mariadb-corporation/mariadb-connector-j 3.4.3 (contains commit 149ec6a62637)

https://github.com/mariadb-corporation/mariadb-connector-j/commit/149ec6a626376214966c01f42d48be1b80d06056
github Patch Available

Cleartext password disclosure to a MITM on the initial-handshake · Advisory · mariadb-corporation/mariadb-connector-j · GitHub

Affected: 2.7.14, 3.3.5, 3.4.3, and 3.5.9. Upgrade to the patched release on your branch (3

https://github.com/mariadb-corporation/mariadb-connector-j/security/advisories/GHSA-g9jj-cgmh-9f38

Vendor Advisories for CVE-2026-55856(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.mariadb.jdbc:mariadb-java-client3.5.0 ... 3.5.8 (9 versions)3.5.9—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 12× in last 7d / 38× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 03:55 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 03:32 UTCEG score recompute
  4. 2026-09-17 19:31 UTCEPSS rescore
  5. 2026-09-17 03:08 UTCEG score recompute
  6. 2026-09-16 14:08 UTCEPSS rescore
  7. 2026-09-16 05:15 UTCEPSS rescore
  8. 2026-09-16 02:14 UTCEG score recompute
  9. 2026-09-15 03:11 UTCEPSS rescore
  10. 2026-09-14 01:26 UTCEG score recompute
  11. 2026-09-13 16:47 UTCEPSS rescore
  12. 2026-09-13 01:03 UTCEG score recompute
  13. 2026-09-12 00:39 UTCEG score recompute
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-11 00:15 UTCEG score recompute
  16. 2026-09-10 09:35 UTCEPSS rescore
  17. 2026-09-09 23:52 UTCEG score recompute
  18. 2026-09-08 22:01 UTCEPSS rescore
  19. 2026-09-07 22:25 UTCEG score recompute
  20. 2026-09-07 16:01 UTCEPSS rescore
  21. 2026-09-06 22:01 UTCEG score recompute
  22. 2026-09-06 13:47 UTCEPSS rescore
  23. 2026-09-05 21:37 UTCEG score recompute
  24. 2026-09-04 21:14 UTCEG score recompute
  25. 2026-09-04 05:07 UTCEPSS rescore
Show 13 more
  1. 2026-09-02 20:23 UTCEG score recompute
  2. 2026-09-02 14:12 UTCEPSS rescore
  3. 2026-09-01 19:53 UTCEG score recompute
  4. 2026-09-01 13:54 UTCEPSS rescore
  5. 2026-09-01 04:40 UTCEPSS rescore
  6. 2026-08-31 19:29 UTCEG score recompute
  7. 2026-08-31 18:55 UTCEG score recompute
  8. 2026-08-31 00:12 UTCEG score recompute
  9. 2026-08-30 19:17 UTCEPSS rescore
  10. 2026-08-30 01:22 UTCEPSS rescore
  11. 2026-08-28 23:25 UTCEG score recompute
  12. 2026-08-28 22:46 UTCEG score recompute
  13. 2026-08-28 22:43 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-55856?
CVE-2026-55856 is a medium vulnerability published on August 28, 2026. MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases. Prior to 2.7.14, 3.3.5, 3.4.3, and 3.5.9, when a Java application connects with sslMode=verify-full or sslMode=verify-ca, supplies a password, and does not configure serverSslCert or trustStore,…
When was CVE-2026-55856 disclosed?
CVE-2026-55856 was first published in the National Vulnerability Database on August 28, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55856 actively exploited?
CVE-2026-55856 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 86.9% of all scored CVEs.
What is the CVSS score of CVE-2026-55856?
CVE-2026-55856 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-55856?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55856, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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