Stack-based buffer overflow in the svcauth_gss_validate function in lib/rpc/svc_auth_gss.c in the RPCSEC_GSS RPC library (librpcsecgss) in MIT Kerberos 5 (krb5) 1.4 through 1.6.2, as used by the Kerberos administration daemon (kadmind) and some third-party applications that use krb5, allows remote attackers to cause a denial of service (daemon crash) and probably execute arbitrary code via a long string in an RPC message.
Conclusion & alert: CVE-2007-3999 is rated High Risk (79.4/100): CVSS Critical severity, with high exploitation likelihood (EPSS 56.12%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +8.27% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize 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 | 2026-06-13 | 47.84% | 56.12% | +8.27% |
| 2 | 2026-06-05 | 48.43% | 47.84% | -0.59% |
| 3 | 2026-05-23 | — | 48.43% | — |
Full EPSS history (28 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 10.0 | 2.0 | HIGH |
|
10.0 | 10.0 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
high | CVE-2007-3999 high priority: Debian including 1 source packages (krb5), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2007-3999 |
gentoo
|
high | CVE-2007-3999: 2 GLSA(s) (200709-01, 200710-01), 2 atom(s) (app-crypt/mit-krb5, net-libs/librpcsecgss); latest impact high. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2007-3999 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2007-3999 |
suse
|
medium | CVE-2007-3999 severity moderate: SUSE including 83 source package names (krb5-1.19.2-2.2, krb5-1.20.1-4.11, …), 179 product×package rows across 32 product lines (HPE Helion OpenStack 8, SUSE Linux Enterprise Desktop 12, … (32 product lines)): Known Not Affected 90, Fixed 89. | https://www.suse.com/security/cve/CVE-2007-3999/ |
ubuntu
|
medium | CVE-2007-3999 medium priority: Ubuntu including 2 source packages (krb5, librpcsecgss), 8 status rows across 4 suites (dapper, edgy, feisty, upstream): released 6, needs-triage 2. | https://ubuntu.com/security/CVE-2007-3999 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| mit | kerberos_5 | 1.4 | cpe:2.3:a:mit:kerberos_5:1.4:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.4.1 | cpe:2.3:a:mit:kerberos_5:1.4.1:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.4.2 | cpe:2.3:a:mit:kerberos_5:1.4.2:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.4.3 | cpe:2.3:a:mit:kerberos_5:1.4.3:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.4.4 | cpe:2.3:a:mit:kerberos_5:1.4.4:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.5 | cpe:2.3:a:mit:kerberos_5:1.5:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.5.1 | cpe:2.3:a:mit:kerberos_5:1.5.1:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.5.2 | cpe:2.3:a:mit:kerberos_5:1.5.2:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.5.3 | cpe:2.3:a:mit:kerberos_5:1.5.3:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.6 | cpe:2.3:a:mit:kerberos_5:1.6:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.6.1 | cpe:2.3:a:mit:kerberos_5:1.6.1:*:*:*:*:*:*:* |
| mit | kerberos_5 | 1.6.2 | cpe:2.3:a:mit:kerberos_5:1.6.2:*:*:*:*:*:*:* |