CVE-2006-6421

Exp

Cross-site scripting (XSS) vulnerability in the private message box implementation (privmsg.php) in phpBB 2.0.x allows remote authenticated users to inject arbitrary web script or HTML via the "Message body" field in a message to a non-existent user.

Published: 2006-12-10 Last update: 2026-04-23 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2006-6421 is rated High Exploit Risk (68.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 2.00%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2006-6421

EDB-ID Source Kind Published Link
29442 exploit_db edb 2007-01-11 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2006-6421

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 2026-06-06 2.27% 2.00% -0.27%
2 2026-04-22 1.94% 2.27% +0.33%
3 2025-07-29 — 1.94% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2006-6421

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 6.8 6.4 [email protected]

Weakness enumeration for CVE-2006-6421

OS Trackers for CVE-2006-6421

vendor priority summary link
alpine — CVE-2006-6421: no source package rows; 0 state rows across 0 repos (none); fixed 0, open 0. https://security.alpinelinux.org/vuln/CVE-2006-6421
ubuntu medium CVE-2006-6421 medium priority: Ubuntu including 1 source packages (phpbb2), 9 status rows across 9 suites (dapper, edgy, feisty, gutsy, hardy, intrepid, jaunty, karmic, upstream): released 4, DNE 2, ignored 2, needs-triage 1. https://ubuntu.com/security/CVE-2006-6421

Affected software / configurations for CVE-2006-6421

Vendor Product Version Raw CPE
phpbb_group phpbb 2.0 cpe:2.3:a:phpbb_group:phpbb:2.0:*:*:*:*:*:*:*
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 2.0.18 cpe:2.3:a:phpbb_group:phpbb:2.0.18:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.19 cpe:2.3:a:phpbb_group:phpbb:2.0.19:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.20 cpe:2.3:a:phpbb_group:phpbb:2.0.20:*:*:*:*:*:*:*
phpbb_group phpbb 2.0.21 cpe:2.3:a:phpbb_group:phpbb:2.0.21:*:*:*:*:*:*:*
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-2006-6421

cvelogic Threat Intelligence