Is there a public exploit for CVE-2026-121619?

No public exploit for CVE-2026-121619 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121619?

CVE-2026-121619 scores CVSS 6.3 (v4.0), rated medium.

What does CVE-2026-121619 affect?

CVE-2026-121619 affects sensiolabs symfony.

6.3 Medium

The Symfony FrameworkBundle framework.trustedproxies option and the HttpFoundation Request::setTrustedProxies() method trust remote clients…

CVE-2026-121619

The Symfony FrameworkBundle framework.trustedproxies option and the HttpFoundation Request::setTrustedProxies() method trust remote clients as reverse proxies when the privateranges shortcut is used, allowing remote attackers to spoof the client IP address, host and scheme in Symfony FrameworkBundle versions 7.1 prior to 7.4.23 and 8.x prior to 8.1.11, and HttpFoundation versions 7.2 prior to 7.4.23 and 8.x prior to 8.1.11. The privateranges and PRIVATESUBNETS keywords resolved to IpUtils::PRIVATESUBNETS, the deny list of NoPrivateNetworkHttpClient, which lists the private and special-purpose prefixes a server must not connect to. Since the fix for CVE-2026-48736 (7.4.13 and 8.0.13), this list also covers the IPv6 prefixes that embed an IPv4 address: IPv4-mapped (::ffff:0:0/96), IPv4-compatible (::/96), 6to4 (2002::/16), Teredo (2001::/32) and NAT64 (64:ff9b::/96). The IPv4-mapped entry has been in the list since the privateranges shortcut was introduced, in 7.1 for framework.trustedproxies and in 7.2 for Request::setTrustedProxies(). Over-blocking is safe for a deny list, but when the same entries are used as the allow list of trusted proxies, they trust remote clients. A client…

Assessment

CVSS: 6.3 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 12 November 2026
Last updated: 12 November 2026
Affected: sensiolabs · symfony
Assigner: Checkmarx

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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