Narcissus is vulnerable to remote code execution via improper input handling in its image configuration workflow. Specifically, the backend.php script fails to sanitize the release parameter before passing it to the configure_image() function. This function invokes PHP’s passthru() with the unsanitized input, allowing attackers to inject arbitrary system commands. Exploitation occurs via a crafted POST request, resulting in command execution under the web server’s context.
https://www.vulncheck.com/advisories/narcissus-image-config-command-injection
https://www.exploit-db.com/exploits/22856
https://www.exploit-db.com/exploits/22709
https://web.archive.org/web/20101127002623/https://narcissus.angstrom-distribution.org/
Published: 2025-08-05
Updated: 2026-04-15
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 9.3
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: Critical
EPSS: 0.01137