CVE-2026-103528 (CVSS 5.4)

Description

Thelia 2.6.0 uses Smarty for email templates without properly restricting access to dangerous PHP functions. An authenticated administrator can inject malicious Smarty expressions into email templates via the messages configuration interface, and when the template is previewed or rendered, functions such as system(), exec(), file_put_contents(), and file_get_contents() can be executed with the privileges of the web process. This allows arbitrary OS command execution, file read/write operations, and RCE on the underlying server.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0052

Probability of exploitation

0.44%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-1336 CWE-1336

References

Other References

https://kb.cert.org/vuls/id/162329

Frequently Asked Questions

What is CVE-2026-103528? +

Thelia 2.6.0 uses Smarty for email templates without properly restricting access to dangerous PHP functions. An authenticated administrator can inject malicious Smarty expressions into email templates via the messages configuration interface, and when the template is previewed or rendered, functions such as system(), exec(), file_put_contents(), and file_get_contents() can be executed with the privileges of the web process. This allows arbitrary OS command execution, file read/write operations, and RCE on the underlying server. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2026-103528? +

CVE-2026-103528 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0052, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-103528? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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