high CVSS 8 EPSS 0.48%

CVE-2026-107821·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, MariaDB insufficiently validated counts, offsets, lengths, and field boundaries in FRM metadata while opening binary FRM files. An attacker able to place a crafted FRM file in the data directory could trigger out-of-bounds reads or writes, crash the server, or potentially execute code. 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
high
Software
MariaDB
Fixed in
13.0.2
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 0.48% — higher than 39% 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-2026-107821 scores 8 on CVSS, so a successful attack would be serious — but at 0.48%, 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: 13.0.1

Until: 13.0.2

Fixed in: 13.0.2

How to fix this CVE

Update MariaDB to version 11.8.9 or later to remediate a critical metadata validation flaw in FRM file handling. This vulnerability allows attackers with filesystem access to the data directory to trigger memory corruption or server crashes by placing specially crafted FRM files. Immediate patching is recommended to prevent potential code execution or denial of service.

sudo dnf update mariadb-server

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check installed MariaDB version with: mariadb --version
  2. Step 2: Verify if MariaDB data directory is accessible to untrusted users by reviewing filesystem permissions: ls -la /var/lib/mysql/ | head -5
  3. Step 3: Search MariaDB error logs for segmentation faults or unexpected crashes: grep -i 'segmentation\|signal 11\|fatal error' /var/log/mysql/error.log
  4. Step 4: Confirm the patch was applied by running mariadb --version again and verifying the version matches 11.8.9 or higher

FAQ

What is CVE-2026-107821?

This vulnerability is an insufficient validation issue in MariaDB's FRM (table definition) file parsing that fails to properly check metadata boundaries, offsets, and field lengths. An attacker who can write to the database directory could craft a malicious FRM file to trigger out-of-bounds memory access, leading to crashes or potential code execution.

Is CVE-2026-107821 being actively exploited?

No, this CVE is not currently listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available, though the high CVSS score warrants prompt remediation.

What versions of MariaDB are affected by CVE-2026-107821?

Affected versions include 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. The fix is available in versions 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2 or later.

How do I check if my server is vulnerable to CVE-2026-107821?

Run 'mariadb --version' to obtain your current version number, then compare it against the affected ranges listed above. If your version is below 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, or 13.0.2 (depending on your release branch), you are vulnerable.

Does Defensia detect CVE-2026-107821?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If MariaDB is installed on a monitored server, CVE-2026-107821 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-2026-85746CVSS 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, 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.
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.

References

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