SQL Injection in Mariadb-Corporation Mariadb-Connector-Nodejs

CVE-2026-55855

MariaDB Connector/Node.js is used to connect applications developed on Node.js to MariaDB and MySQL databases. Prior to 3.2.4, 3.3.3, 3.4.6, and 3.5.3, MariaDB Connector/Node.js permits SQL injection when attacker-controlled Buffer parameters are escaped client-side under the big5, gbk, sjis, cp932, or gb18030 client character sets. PacketOutputStream.writeBufferEscape in lib/io/packet-output-stream.js escaped bytes without the charset-aware getMbRecognizer logic in lib/misc/charset-mb.js. The server SQL lexer runs my_ismbchar before escape processing, so an attacker-controlled lead byte can consume the inserted 0x5C backslash as a multibyte trail byte and leave the following 0x27 quote unescaped, terminating the string literal and allowing arbitrary SQL. The default utf8mb4 character set and parameters sent through the execute binary prepared-statement path are not affected. Successful exploitation can expose or modify data available to the database account. This issue is fixed in versions 3.2.4, 3.3.3, 3.4.6, and 3.5.3.

Vulnerability class: SQL Injection

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-55855: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55855?
CVE-2026-55855 is a medium-severity vulnerability in Mariadb-Corporation Mariadb-Connector-Nodejs, classified under SQL Injection. CVSS score: 6.5/10. Published 2026-08-28.
How severe is CVE-2026-55855?
Medium severity. CVSS v3 base score is 6.5 out of 10.