CVE-2026-48736 Sensiolabs CVE debrief

Who should care

Users of Symfony framework versions 5.4.0 to 5.4.53, 6.4.0 to 6.4.41, 7.0.0 to 7.4.13, and 8.0.0 to 8.0.13 should be aware of this vulnerability. Affected operators, platforms, vulnerability-management, and security teams should review and update affected systems and applications, monitor for suspicious activity, and implement compensating controls.

Technical summary

Symfony, a PHP framework for web and console applications, had a vulnerability in its NoPrivateNetworkHttpClient and IpUtils::PRIVATE_SUBNETS implementation. The issue allowed attacker-supplied URLs to represent private IPv4 targets, which were not blocked by IpUtils::isPrivateIp(). This vulnerability affected versions 5.4.0 to 5.4.53, 6.4.0 to 6.4.41, 7.0.0 to 7.4.13, and 8.0.0 to 8.0.13. The vulnerability is fixed in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13.

Defensive priority

Medium priority due to the CVSS score of 6.9 and the potential for attackers to exploit this vulnerability.

Recommended defensive actions

• Update Symfony to version 5.4.53, 6.4.41, 7.4.13, or 8.0.13
• Review and update affected systems and applications
• Monitor for suspicious activity
• Implement compensating controls
• Verify inventory of systems and applications
• Review relevant monitoring, detection, and logs for exposed assets
• Track exceptions and retest remediated assets

Evidence notes

The CVE record and NVD entry provide information on the vulnerability and affected versions. The vendor, Sensiolabs, has provided patches and release notes for the affected versions. Evidence limits suggest that further verification is needed to confirm affected scope and severity. Defenders should verify inventory of systems and applications, review compensating controls, and monitor for suspicious activity. Additional review of vendor documentation and security advisories may be necessary to fully understand the vulnerability.

Official resources