CVE-2005-3420

usercp_register.php in phpBB 2.0.17 allows remote attackers to modify regular expressions and execute PHP code via the signature_bbcode_uid parameter, as demonstrated by injecting an "e" modifier into a preg_replace statement.

Published: 2005-11-01 Last update: 2026-04-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2005-3420 is rated Moderate Risk (58.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.32%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2005-3420

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 3.05% 2.32% -0.73%
2 2025-03-29 2.32% 3.05% +0.73%
3 2025-03-17 — 2.32% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2005-3420

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2005-3420

OS Trackers for CVE-2005-3420

vendor priority summary link
ubuntu medium CVE-2005-3420 medium priority: Ubuntu including 1 source packages (phpbb2), 4 status rows across 4 suites (dapper, edgy, feisty, upstream): released 3, needs-triage 1. https://ubuntu.com/security/CVE-2005-3420

Affected software / configurations for CVE-2005-3420

Vendor Product Version Raw CPE
phpbb_group phpbb 2.0.0 cpe:2.3:a:phpbb_group:phpbb:2.0.0:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.1 cpe:2.3:a:phpbb_group:phpbb:2.0.1:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.2 cpe:2.3:a:phpbb_group:phpbb:2.0.2:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.3 cpe:2.3:a:phpbb_group:phpbb:2.0.3:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.4 cpe:2.3:a:phpbb_group:phpbb:2.0.4:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.5 cpe:2.3:a:phpbb_group:phpbb:2.0.5:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.6 cpe:2.3:a:phpbb_group:phpbb:2.0.6:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.6c cpe:2.3:a:phpbb_group:phpbb:2.0.6c:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.6d cpe:2.3:a:phpbb_group:phpbb:2.0.6d:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.7 cpe:2.3:a:phpbb_group:phpbb:2.0.7:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.7a cpe:2.3:a:phpbb_group:phpbb:2.0.7a:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.8 cpe:2.3:a:phpbb_group:phpbb:2.0.8:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.8a cpe:2.3:a:phpbb_group:phpbb:2.0.8a:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.9 cpe:2.3:a:phpbb_group:phpbb:2.0.9:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.10 cpe:2.3:a:phpbb_group:phpbb:2.0.10:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.11 cpe:2.3:a:phpbb_group:phpbb:2.0.11:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.12 cpe:2.3:a:phpbb_group:phpbb:2.0.12:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.13 cpe:2.3:a:phpbb_group:phpbb:2.0.13:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.14 cpe:2.3:a:phpbb_group:phpbb:2.0.14:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.15 cpe:2.3:a:phpbb_group:phpbb:2.0.15:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.16 cpe:2.3:a:phpbb_group:phpbb:2.0.16:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.17 cpe:2.3:a:phpbb_group:phpbb:2.0.17:*:*:*:*:*:*:*
phpbb_group phpbb 2.0_beta1 cpe:2.3:a:phpbb_group:phpbb:2.0_beta1:*:*:*:*:*:*:*
phpbb_group phpbb 2.0_rc1 cpe:2.3:a:phpbb_group:phpbb:2.0_rc1:*:*:*:*:*:*:*
phpbb_group phpbb 2.0_rc2 cpe:2.3:a:phpbb_group:phpbb:2.0_rc2:*:*:*:*:*:*:*
phpbb_group phpbb 2.0_rc3 cpe:2.3:a:phpbb_group:phpbb:2.0_rc3:*:*:*:*:*:*:*
phpbb_group phpbb 2.0_rc4 cpe:2.3:a:phpbb_group:phpbb:2.0_rc4:*:*:*:*:*:*:*

References for CVE-2005-3420

cvelogic Threat Intelligence