critical CVSS 9.9 EPSS 0.63%

CVE-2026-85746·MariaDB vulnerability

MariaDB server is a community developed fork of MySQL server. From 10.6.1 until 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2, ST_AsText can write beyond an allocated output buffer when converting deeply nested GeometryCollections because recursive WKT serialization does not account for bytes consumed or reserve sufficient space. A low-privileged remote attacker can submit a specially crafted GIS object to corrupt memory and potentially achieve code execution when combined with another vulnerability. This issue is fixed in versions 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2.

Severity
critical
Software
MariaDB
Fixed in
12.3.3
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.63% — higher than 49% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-85746 scores 9.9 on CVSS, so a successful attack would be serious — but at 0.63%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 12.3.1

Until: 12.3.3

Fixed in: 12.3.3

How to fix this CVE

MariaDB versions prior to 11.8.9 contain a critical buffer overflow in the ST_AsText function when processing deeply nested GeometryCollections, allowing remote attackers with database access to trigger memory corruption and potential code execution. Immediately upgrade MariaDB to version 11.8.9 or later across all affected systems. After upgrading, restart the MariaDB service and validate that GIS queries no longer cause unexpected behavior.

sudo dnf update mariadb-server

Defensia detects this vulnerability

How to check if you are affected

  1. Check installed MariaDB version: mysql -V or mariadb -V
  2. Query the database for version details: SELECT VERSION(); inside the MariaDB client
  3. Search MariaDB error logs for ST_AsText errors or segmentation faults: grep -i 'st_astext\|segmentation\|buffer overflow' /var/log/mariadb/error.log
  4. Verify the fix by confirming the version is 11.8.9 or higher and restart the service: sudo systemctl restart mariadb

FAQ

What is CVE-2026-85746?

A critical buffer overflow vulnerability in MariaDB's ST_AsText function that fails to properly allocate memory when recursively converting deeply nested GeometryCollections to Well-Known Text format, enabling remote authenticated attackers to corrupt memory and potentially execute arbitrary code.

Is CVE-2026-85746 being actively exploited?

No, there is currently no evidence of active exploitation or publicly available exploits for this vulnerability, but given its critical CVSS score of 9.0 and network accessibility, patching should be prioritized immediately.

What versions of MariaDB are affected by CVE-2026-85746?

MariaDB versions 10.6.1 through 10.6.27, 10.11.0 through 10.11.18, 11.4.0 through 11.4.12, 11.8.0 through 11.8.8, 12.3.0 through 12.3.2, and 13.0.0 through 13.0.1 are vulnerable.

How do I check if my server is vulnerable to CVE-2026-85746?

Run 'mariadb --version' or connect to the server and execute 'SELECT VERSION();' — if the version is below 11.8.9 (or the patched version for your branch), your server is vulnerable.

Does Defensia detect CVE-2026-85746?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If MariaDB is installed on a monitored server, CVE-2026-85746 will appear in your dashboard with remediation steps.

Related MariaDB CVEs

CVE-2026-49261CVSS 10MariaDB server is a community developed fork of MySQL server. Versions 10.6.1 through 10.6.26, 10.11.1 through 10.11.17, 11.4.1 through 11.4.11, 11.8.1 through 11.8.7, and 12.3.1 with `wsrep_notify_cmd` enabled would execute shell commands embedded in the name of the joiner node. This is fixed in 10.6.27, 10.11.18, 11.4.12, 11.8.8, and 12.3.2. As a workaround, anyone who cannot upgrade now should disable `wsrep_notify_cmd`.
CVE-2026-85748CVSS 9.9MariaDB server is a community developed fork of MySQL server. From 12.3.1 until 12.3.3 and 13.0.2, SYS_REFCURSOR handling is affected because cursor-array reallocation can leave stale references in routine contexts. A low-privileged attacker can open a large number of SYS_REFCURSORs and then fetch one to trigger a use-after-free that can enable remote code execution when combined with another vulnerability. This issue is fixed in versions 12.3.3 and 13.0.2.
CVE-2026-92262CVSS 9.9MariaDB server is a community developed fork of MySQL server. From 10.6.1 until 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2, the #mysql50# bypass prefix is affected because it allows the #mysql50# prefix to bypass normal table-name filesystem encoding. An attacker can trigger the issue with a table name using the #mysql50# prefix, then use a #mysql50# table name to access files under their legacy unencoded name and cause crashes, data corruption, data exfiltration, or remote code execution. This issue is fixed in versions 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2.
CVE-2026-44170CVSS 9.8MariaDB server is a community developed fork of MySQL server. From versions 10.6.1 to before 10.6.26, 10.11.1 to before 10.11.17, 11.4.1 to before 11.4.11, 11.8.1 to before 11.8.7, and 12.3.1, MariaDB on WIndows with installed CONNECT engine and enabled REST support interpolated table HTTP attribute into the curl command line without proper sanitizing. This allows the user to execute shell commands on the server. This issue has been patched in versions 10.6.26, 10.11.17, 11.4.11, 11.8.7, and 12.3.2.
CVE-2026-22730CVSS 8.8A critical SQL injection vulnerability in Spring AI's MariaDBFilterExpressionConverter allows attackers to bypass metadata-based access controls and execute arbitrary SQL commands. The vulnerability exists due to missing input sanitization.

References

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