Deserialization of Untrusted Data in Qwik - CVE-2026-27971
Published: March 4, 2026
Vulnerability identifier: #VU123517
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-27971
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Builder.io
Affected software:
Qwik
Qwik
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to insecure input validation when processing serialized data in the server$ RPC mechanism. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
How to mitigate CVE-2026-27971
Install updates from vendor's website.