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CVE-2026-109413: Symfony: Unbounded Recursion in the YAML Inline Lexer Lets a Single Document Crash the Process

high Affects symfony/symfony, symfony/yaml. Feed 2026.10.29.3, updated 2026-10-29; published .

Symfony: Unbounded Recursion in the YAML Inline Lexer Lets a Single Document Crash the Process

Package
symfony/symfony Composer
Affected versions
>=2.0.0 and <5.4.54 or >=6.0.0 and <6.4.45 or >=7.0.0 and <7.4.18 or >=8.0.0 and <8.1.6 or >=2.0.0 and <3.0.0 or >=3.0.0 and <4.0.0 or >=4.0.0 and <5.0.0 or >=5.0.0 and <5.1.0 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.3.0 or >=5.3.0 and <5.4.0 or >=5.4.0 and <5.4.54 or >=6.0.0 and <6.1.0 or >=6.1.0 and <6.2.0 or >=6.2.0 and <6.3.0 or >=6.3.0 and <6.4.0 or >=6.4.0 and <6.4.45 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.18 or >=8.0.0 and <8.1.0 or >=8.1.0 and <8.1.6
Fixed in
5.4.54, 6.4.45, 7.4.18, 8.1.6
Severity
high
Exploitation
not on CISA KEV · EPSS 0% (33.7th percentile)
Published
2026-10-27
Source
osv.dev

References

Symfony: Unbounded Recursion in the YAML Inline Lexer Lets a Single Document Crash the Process

Package
symfony/yaml Composer
Affected versions
>=2.0.0 and <5.4.54 or >=6.0.0 and <6.4.45 or >=7.0.0 and <7.4.18 or >=8.0.0 and <8.1.6 or >=2.0.0 and <3.0.0 or >=3.0.0 and <4.0.0 or >=4.0.0 and <5.0.0 or >=5.0.0 and <5.1.0 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.3.0 or >=5.3.0 and <5.4.0 or >=5.4.0 and <5.4.54 or >=6.0.0 and <6.1.0 or >=6.1.0 and <6.2.0 or >=6.2.0 and <6.3.0 or >=6.3.0 and <6.4.0 or >=6.4.0 and <6.4.45 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.18 or >=8.0.0 and <8.1.0 or >=8.1.0 and <8.1.6
Fixed in
5.4.54, 6.4.45, 7.4.18, 8.1.6
Severity
high
Exploitation
not on CISA KEV · EPSS 0% (33.7th percentile)
Published
2026-10-27
Source
osv.dev

References

CWE-674
NVD recordsymfony/symfony advisoriessymfony/yaml advisories

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