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CVE-2021-41267: Webcache Poisoning in symfony/http-kernel

medium Affects symfony/http-kernel, symfony/symfony. Feed 2026.10.29.4, updated 2026-10-29; published ; advisory modified .

Webcache Poisoning in symfony/http-kernel

Package
symfony/http-kernel Composer
Affected versions
>=5.2.0 and <5.3.12 or >=5.2.0 and <5.3.0 or >=5.3.0 and <5.3.12
Fixed in
5.3.12
Severity
medium  CVSS 6.5
Exploitation
not on CISA KEV · EPSS 1% (69.9th percentile)
Published
2021-11-24
Source
osv.dev

References

Webcache Poisoning in symfony/http-kernel

Package
symfony/symfony Composer
Affected versions
>=5.2.0 and <5.3.12 or >=5.2.0 and <5.3.0 or >=5.3.0 and <5.3.12
Fixed in
5.3.12
Severity
medium  CVSS 6.5
Exploitation
not on CISA KEV · EPSS 1% (69.9th percentile)
Published
2021-11-24
Source
osv.dev

References

CWE-444
NVD recordsymfony/http-kernel advisoriessymfony/symfony advisories

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