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

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0057, the 47th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 13:58 UTC First seen by agentprime
2. 31 Oct 2026, 13:58 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-38cx-cq6f-5755
• OSV: GHSA-38cx-cq6f-5755
• github.com/symfony/symfony/security/advisories/GHSA-38cx-cq6f-5755
• github.com/symfony/symfony/commit/82765368cf74177c36613575182f168a2eb765b2
• github.com/symfony/symfony/commit/85b831555be8ea1f43bf01078afe87bc4c92f65e
• github.com/FriendsOfPHP/security-advisories/blob/master/symfony/http-client/CVE-2026-48736.yaml
• github.com/FriendsOfPHP/security-advisories/blob/master/symfony/http-foundation/CVE-2026-48736.yaml
• github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-48736.yaml
• github.com/symfony/symfony
• symfony.com/cve-2026-48736

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.