CVE-2021-21424: Prevent user enumeration using Guard or the new Authenticator-based Security

medium Affects lexik/jwt-authentication-bundle, symfony/maker-bundle, symfony/security, symfony/security-core, symfony/security-guard, symfony/security-http and 1 more. Feed 2026.10.29.4, updated 2026-10-29; published ; advisory modified .

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
lexik/jwt-authentication-bundle Composer
Affected versions
>=2.0.0 and <2.10.7 or >=2.11.0 and <2.11.3 or >=2.0.0 and <2.1.0 or >=2.1.0 and <2.2.0 or >=2.2.0 and <2.3.0 or >=2.3.0 and <2.4.0 or >=2.4.0 and <2.5.0 or >=2.5.0 and <2.6.0 or >=2.6.0 and <2.7.0 or >=2.7.0 and <2.8.0 or >=2.8.0 and <2.9.0 or >=2.9.0 and <2.10.0 or >=2.10.0 and <2.10.7
Fixed in
2.10.7, 2.11.3
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/maker-bundle Composer
Affected versions
>=1.27.0 and <1.29.2 or >=1.30.0 and <1.31.1 or >=1.27.0 and <1.28.0 or >=1.28.0 and <1.29.0 or >=1.29.0 and <1.29.2 or >=1.30.0 and <1.31.0 or >=1.31.0 and <1.31.1
Fixed in
1.29.2, 1.31.1
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/security Composer
Affected versions
>=5.0.0 and <5.2.8 or >=2.8.0 and <3.4.49 or >=4.0.0 and <4.4.24 or >=2.8.0 and <3.0.0 or >=3.0.0 and <3.1.0 or >=3.1.0 and <3.2.0 or >=3.2.0 and <3.3.0 or >=3.3.0 and <3.4.0 or >=3.4.0 and <3.4.49 or >=4.0.0 and <4.1.0 or >=4.1.0 and <4.2.0 or >=4.2.0 and <4.3.0 or >=4.3.0 and <4.4.0 or >=4.4.0 and <4.4.24
Fixed in
5.2.8, 3.4.49, 4.4.24
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/security-core Composer
Affected versions
>=2.8.0 and <3.4.48 or >=4.0.0 and <4.4.23 or >=5.0.0 and <5.2.8 or >=2.8.0 and <3.0.0 or >=3.0.0 and <3.1.0 or >=3.1.0 and <3.2.0 or >=3.2.0 and <3.3.0 or >=3.3.0 and <3.4.0 or >=3.4.0 and <3.4.49 or >=4.0.0 and <4.1.0 or >=4.1.0 and <4.2.0 or >=4.2.0 and <4.3.0 or >=4.3.0 and <4.4.0 or >=4.4.0 and <4.4.24 or >=5.0.0 and <5.1.0 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.2.9
Fixed in
3.4.49, 4.4.24, 5.2.9
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/security-guard Composer
Affected versions
>=2.8.0 and <3.4.48 or >=4.0.0 and <4.4.23 or >=5.0.0 and <5.2.8 or >=2.8.0 and <3.0.0 or >=3.0.0 and <3.1.0 or >=3.1.0 and <3.2.0 or >=3.2.0 and <3.3.0 or >=3.3.0 and <3.4.0 or >=3.4.0 and <3.4.48 or >=4.0.0 and <4.1.0 or >=4.1.0 and <4.2.0 or >=4.2.0 and <4.3.0 or >=4.3.0 and <4.4.0 or >=4.4.0 and <4.4.23 or >=5.0.0 and <5.1.0 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.2.8
Fixed in
3.4.48, 4.4.23, 5.2.8
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/security-http Composer
Affected versions
>=5.1.0 and <5.2.8 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.2.8
Fixed in
5.2.8
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

Prevent user enumeration using Guard or the new Authenticator-based Security

Package
symfony/symfony Composer
Affected versions
>=2.8.0 and <3.4.49 or >=4.0.0 and <4.4.24 or >=5.0.0 and <5.2.9 or >=2.8.0 and <3.0.0 or >=3.0.0 and <3.1.0 or >=3.1.0 and <3.2.0 or >=3.2.0 and <3.3.0 or >=3.3.0 and <3.4.0 or >=3.4.0 and <3.4.49 or >=4.0.0 and <4.1.0 or >=4.1.0 and <4.2.0 or >=4.2.0 and <4.3.0 or >=4.3.0 and <4.4.0 or >=4.4.0 and <4.4.24 or >=5.0.0 and <5.1.0 or >=5.1.0 and <5.2.0 or >=5.2.0 and <5.2.9
Fixed in
3.4.49, 4.4.24, 5.2.9
Severity
medium  CVSS 5.3
Exploitation
not on CISA KEV · EPSS 2% (76.4th percentile)
Published
2021-05-13
Source
osv.dev

References

CWE-200CWE-203
NVD recordlexik/jwt-authentication-bundle advisoriessymfony/maker-bundle advisoriessymfony/security advisoriessymfony/security-core advisoriessymfony/security-guard advisoriessymfony/security-http advisories

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