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CVE PROGRAM SOURCE RECORD8.7 High

CVE-2026-109449

Symfony: Unbounded Nesting in the Expression Parser Lets Untrusted Expressions Crash the Process

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Status
Published
Published
Updated
Assigning organization
Checkmarx

Description

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

sensiolabs symfony

Default version status: unaffected

  • 0 to < v5.4.54affected
  • v6.0.0-BETA1 to < v6.4.48affected
  • v7.0.0-BETA1 to < v7.4.21affected
  • v8.0.0-BETA1 to < v8.1.9affected

References