What is CVE-2026-71291?

CVE-2026-71291 is a high-severity vulnerability in Bolt Core, classified under Improper Neutralization of Special Elements Used in a Template Engine. CVSS score: 8.8/10. Published 2026-08-05.

How severe is CVE-2026-71291?

High severity. CVSS v3 base score is 8.8 out of 10.

Vulnerability in Bolt Core

CVE-2026-71291

Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.

EPSS: 0.003 (23.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Bolt Core — versions 0

Weakness classification (CWE)

CWE-1336 — Improper Neutralization of Special Elements Used in a Template Engine

References

309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c (third-party-advisory)
309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c (third-party-advisory)

Frequently asked questions

What is CVE-2026-71291?: CVE-2026-71291 is a high-severity vulnerability in Bolt Core, classified under Improper Neutralization of Special Elements Used in a Template Engine. CVSS score: 8.8/10. Published 2026-08-05.
How severe is CVE-2026-71291?: High severity. CVSS v3 base score is 8.8 out of 10.