Servers and applications
CVE-2006-4020 scanf.c in PHP 5.1.4 and earlier, and 4.4.3 and earlier, allows context-dependent attackers to execute arbitrary code via a sscanf PHP function call that performs argument swapping, which increments an index past the end of an array and triggers a buffer over-read.
Severity Medium 4.6
Published 8 Aug 2006
Last changed 16 Jun 2026
Added to UpHeron 14 Oct 2026 Exploit chance 2% in the next 30 daysHigher than 81% of CVEs. EPSS by FIRST , 12 Nov 2026
Attack Needs local access · No login needed
Attacker can Read some data · Change some data · Slow it down
CVSS vector AV:L/AC:L/Au:N/C:P/I:P/A:P
Sources NVD Affected software Software Affected versions PHPServers and applications · cpe:a:php:php Version 5.1.4 Version 5.1.2 Version 5.1.1 Version 5.1.0 All 65 release lines Version 4.0-beta1 Version 4.0-beta2 Version 4.0-beta3 Version 4.0-beta4 Version 4.0-beta_4_patch1 Version 4.0-rc1 Version 4.0-rc2 Version 4.0 Version 4.0.1 Version 4.0.1-patch1 Version 4.0.1-patch2 Version 4.0.2 Version 4.0.3 Version 4.0.3-patch1 Version 4.0.4 Version 4.0.4-patch1 Version 4.0.5 Version 4.0.6 Version 4.0.7-rc1 Version 4.0.7-rc2 Version 4.0.7-rc3 Version 4.0.7 Version 4.1.0 Version 4.1.1 Version 4.1.2 Version 4.2 Version 4.2.1 Version 4.2.2 Version 4.2.3 Version 4.3.0 Version 4.3.1 Version 4.3.2 Version 4.3.3 Version 4.3.4 Version 4.3.5 Version 4.3.6 Version 4.3.7 Version 4.3.8 Version 4.3.9 Version 4.3.10 Version 4.3.11 Version 4.4.0 Version 4.4.1 Version 4.4.2 Version 4.4.3 Version 5.0.0-beta1 Version 5.0.0-beta2 Version 5.0.0-beta3 Version 5.0.0-beta4 Version 5.0-rc1 Version 5.0.0-rc1 Version 5.0-rc2 Version 5.0.0-rc2 Version 5.0-rc3 Version 5.0.0-rc3 Version 5.0.0 Version 5.0.1 Version 5.0.2 Version 5.0.3 Version 5.0.4 Version 5.0.5 Version 5.1.0 Version 5.1.1 Version 5.1.2 Version 5.1.4
References NVD https://nvd.nist.gov/vuln/detail/CVE-2006-4020 CVE.org https://www.cve.org/CVERecord?id=CVE-2006-4020