CVE-2026-109449

In Symfony Expression Language versions prior to 5.4.54, 6.4.48, 7.4.21, and 8.1.9, the parser of the ExpressionLanguage component built its node tree with no bound on its depth. An expression made of tens of thousands of nested unary operators, array literals, binary operators or property accesses crashed the PHP process, while the tree was being freed. #[Assert\ExpressionSyntax] passes the validated value to ExpressionLanguage::lint(), so an application validating expressions written by its users could be crashed by a single request, and so could any code parsing untrusted expressions. This issue affects symfony/expression-language through v5.4.53, v6.0.0-BETA1 through v6.4.47, v7.0.0-BETA1 through v7.4.20, and v8.0.0-BETA1 through v8.1.8.

CVSS

No CVSS.

References

Link	Resource
https://github.com/symfony/symfony/pull/65690
https://github.com/symfony/symfony/pull/66720
https://github.com/symfony/symfony/pull/66723
https://github.com/symfony/symfony/security/advisories/GHSA-7rpj-w9pf-39rr
https://symfony.com/blog/cve-2026-109449-unbounded-nesting-in-the-expression-parser-lets-untrusted-expressions-crash-the-process

Configurations

No configuration.

History

15 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 16:17

Updated : 2026-10-16 16:00

NVD link : CVE-2026-109449

Mitre link : CVE-2026-109449

CVE.ORG link : CVE-2026-109449

JSON object : View

Products Affected

No product.

CWE

CWE-674

Uncontrolled Recursion

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