CVE-2026-48736: Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient

medium Affects symfony/http-client, symfony/http-foundation, symfony/symfony. Feed 2026.10.29.4, updated 2026-10-29; published 2026-06-15; advisory modified 2026-09-10.

Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient

Package: symfony/http-client Composer
Affected versions: >=5.4.0 and <5.4.53
Fixed in: 5.4.53
Severity: medium
Exploitation: not on CISA KEV · EPSS 1% (47.1th percentile)
Published: 2026-06-15
Source: osv.dev

References

Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient

Package: symfony/http-foundation Composer
Affected versions: >=6.4.0 and <6.4.41 or >=7.0.0 and <7.4.13 or >=8.0.0 and <8.0.13 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 <7.4.13
Fixed in: 6.4.41, 7.4.13, 8.0.13
Severity: medium
Exploitation: not on CISA KEV · EPSS 1% (47.1th percentile)
Published: 2026-06-15
Source: osv.dev

References

Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient

Package: symfony/symfony Composer
Affected versions: >=5.4.0 and <5.4.53 or >=6.4.0 and <6.4.41 or >=7.0.0 and <7.4.13 or >=8.0.0 and <8.0.13 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 <7.4.13
Fixed in: 5.4.53, 6.4.41, 7.4.13, 8.0.13
Severity: medium
Exploitation: not on CISA KEV · EPSS 1% (47.1th percentile)
Published: 2026-06-15
Source: osv.dev

References

CWE-184 CWE-918

NVD record symfony/http-client advisories symfony/http-foundation advisories symfony/symfony advisories

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