What is CVE-2026-48806?

CVE-2026-48806 is a critical-severity vulnerability in Symfony Twig, classified under Protection Mechanism Failure. CVSS score: 9.1/10. Published 2026-07-14.

How severe is CVE-2026-48806?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Auth bypass in Symfony Twig

CVE-2026-48806

Twig is a template language for PHP. Prior to 3.27.0, ArrayExpression does not guard dynamic mapping keys that are coerced to strings, allowing PHP to invoke __toString() on a Stringable object used as a mapping key without calling SandboxExtension::ensureToStringAllowed(). This issue is fixed in version 3.27.0.

Published 2026-07-14 · last modified 2026-07-17.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (35.1th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 35th percentile — 35.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Symfony Twig
Twigphp Twig — versions < 3.27.0

Weakness classification (CWE)

References

github.com/twigphp/Twig/security/advisories/GHSA-5v5v-ww74-355v (Vendor Advisory)
github.com/twigphp/Twig/commit/9ff41014639ef0e8eb50ac7669191c309d863105 (Patch)
github.com/twigphp/Twig/releases/tag/v3.27.0 (Release Notes)

Frequently asked questions

What is CVE-2026-48806?: CVE-2026-48806 is a critical-severity vulnerability in Symfony Twig, classified under Protection Mechanism Failure. CVSS score: 9.1/10. Published 2026-07-14.
How severe is CVE-2026-48806?: Critical severity. CVSS v3 base score is 9.1 out of 10.