The vfprintf function in stdio-common/vfprintf.c in GNU C Library (aka glibc) 2.5, 2.12, and probably other versions does not "properly restrict the use of" the alloca function when allocating the SPECS array, which allows context-dependent attackers to bypass the FORTIFY_SOURCE format-string protection mechanism and cause a denial of service (crash) or possibly execute arbitrary code via a crafted format string using positional parameters and a large number of format specifiers, a different vulnerability than CVE-2012-3404 and CVE-2012-3405.
Conclusion & alert: CVE-2012-3406 is rated Moderate Risk (59.7/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 3.16%). Core evidence: EPSS rose +2.29% over the last day, indicating growing attacker interest. 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 | 2026-06-15 | 0.87% | 3.16% | +2.29% |
| 2 | 2025-12-28 | 1.13% | 0.87% | -0.26% |
| 3 | 2025-12-27 | — | 1.13% | — |
Full EPSS history (17 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.8 | 2.0 | MEDIUM |
|
8.6 | 6.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
low | CVE-2012-3406 low priority: Debian including 1 source packages (glibc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2012-3406 |
gentoo
|
normal | CVE-2012-3406: 1 GLSA(s) (201503-04), 1 atom(s) (sys-libs/glibc); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2012-3406 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2012-3406 |
suse
|
medium | CVE-2012-3406 severity moderate: SUSE including 307 source package names (glibc, glibc-2.11.1-0.46.1, …), 592 product×package rows across 72 product lines (HPE Helion OpenStack 8, SUSE CaaS Platform 4.0, … (72 product lines)): Fixed 395, Known Not Affected 197. | https://www.suse.com/security/cve/CVE-2012-3406/ |
ubuntu
|
medium | CVE-2012-3406 medium priority: Ubuntu including 2 source packages (eglibc, glibc), 12 status rows across 6 suites (hardy, lucid, natty, oneiric, precise, upstream): DNE 5, released 5, needs-triage 2. | https://ubuntu.com/security/CVE-2012-3406 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| gnu | glibc | 2.5 | cpe:2.3:a:gnu:glibc:2.5:*:*:*:*:*:*:* |
| gnu | glibc | 2.12 | cpe:2.3:a:gnu:glibc:2.12:*:*:*:*:*:*:* |
| redhat | enterprise_virtualization | 3.0 | cpe:2.3:a:redhat:enterprise_virtualization:3.0:*:*:*:*:*:*:* |
| canonical | ubuntu_linux | 8.04 | cpe:2.3:o:canonical:ubuntu_linux:8.04:-:lts:*:*:*:*:* |
| canonical | ubuntu_linux | 10.04 | cpe:2.3:o:canonical:ubuntu_linux:10.04:-:lts:*:*:*:*:* |
| canonical | ubuntu_linux | 11.04 | cpe:2.3:o:canonical:ubuntu_linux:11.04:*:*:*:*:*:*:* |
| canonical | ubuntu_linux | 11.10 | cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:* |
| canonical | ubuntu_linux | 12.04 | cpe:2.3:o:canonical:ubuntu_linux:12.04:-:lts:*:*:*:*:* |
| redhat | enterprise_linux | 5 | cpe:2.3:o:redhat:enterprise_linux:5:*:*:*:*:*:*:* |
| redhat | enterprise_linux | 6.0 | cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* |