CVE-2026-48736CWE-184CWE-918

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

Medium · published July 14, 2026

CVSS v4.0
6.9
EPSS
1%
Percentile
46.5
In the wild
Unconfirmed
What it is

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 5.4.0 to 5.4.53, 6.4.41, 7.4.13, and 8.0.13, NoPrivateNetworkHttpClient and IpUtils::PRIVATE_SUBNETS omitted IPv6 transition prefixes such as 6to4, NAT64, Teredo, and IPv4-compatible IPv6, allowing attacker-supplied URLs to represent private IPv4 targets in forms that IpUtils::isPrivateIp() did not block. This issue is fixed in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13.

The record
Technical detail
CVSS v4.0
6.9 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
EPSS
0.00570 · 46.5th percentile
Weaknesses
CWE-184 · Incomplete List of Disallowed Inputs; CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-07-14T19:09Z
EPSS history
Timeline
  • 14 JUL 19:09Z
    Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient
    cvelistv5