Integer overflow in the CIDAFM function in X.Org 6.8.2 and XFree86 X server allows local users to execute arbitrary code via crafted Adobe Font Metrics (AFM) files with a modified number of character metrics (StartCharMetrics), which leads to a heap-based buffer overflow.
Conclusion & alert: CVE-2006-3739 is rated Moderate Risk (42.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.18%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
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 | 2025-07-19 | 0.09% | 0.18% | +0.08% |
| 2 | 2023-11-08 | 0.05% | 0.09% | +0.05% |
| 3 | 2023-03-07 | — | 0.05% | — |
Full EPSS history (4 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.2 | 2.0 | HIGH |
|
3.9 | 10.0 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2006-3739 not yet assigned priority: Debian including 1 source packages (libxfont), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2006-3739 |
gentoo
|
high | CVE-2006-3739: 1 GLSA(s) (200609-07), 2 atom(s) (x11-base/xorg-x11, x11-libs/libXfont); latest impact high. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2006-3739 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2006-3739 |
ubuntu
|
medium | CVE-2006-3739 medium priority: Ubuntu including 2 source packages (libxfont, xorg), 8 status rows across 4 suites (dapper, edgy, feisty, upstream): not-affected 4, released 3, needs-triage 1. | https://ubuntu.com/security/CVE-2006-3739 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| x.org | x.org | 6.8.2 | cpe:2.3:a:x.org:x.org:6.8.2:*:*:*:*:*:*:* |
| xfree86_project | xfree86_x | — | cpe:2.3:a:xfree86_project:xfree86_x:*:*:*:*:*:*:*:* |