The ssl_Do1stHandshake function in sslsecur.c in libssl in Mozilla Network Security Services (NSS) before 3.15.4, when the TLS False Start feature is enabled, allows man-in-the-middle attackers to spoof SSL servers by using an arbitrary X.509 certificate during certain handshake traffic.
Conclusion & alert: CVE-2013-1740 is rated High Exploit Risk (66.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.93%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: 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.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
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 | 1.00% | 1.93% | +0.93% |
| 2 | 2026-03-27 | 1.40% | 1.00% | -0.40% |
| 3 | 2026-02-22 | — | 1.40% | — |
Full EPSS history (14 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.8 | 2.0 | MEDIUM |
|
8.6 | 4.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2013-1740 not yet assigned priority: Debian including 1 source packages (nss), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2013-1740 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2013-1740 |
suse
|
medium | CVE-2013-1740 severity moderate: SUSE including 151 source package names (libfreebl3-3.101.2-slfo.1.1_1.6, libfreebl3-3.112-160000.2.2, …), 242 product×package rows across 28 product lines (SUSE Linux Enterprise Desktop 12, SUSE Linux Enterprise Desktop 12 SP1, … (28 product lines)): Fixed 242. | https://www.suse.com/security/cve/CVE-2013-1740/ |
ubuntu
|
medium | CVE-2013-1740 medium priority: Ubuntu including 1 source packages (nss), 6 status rows across 6 suites (lucid, precise, quantal, raring, saucy, upstream): released 5, ignored 1. | https://ubuntu.com/security/CVE-2013-1740 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| mozilla | network_security_services | <= 3.15.3 | cpe:2.3:a:mozilla:network_security_services:*:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.2 | cpe:2.3:a:mozilla:network_security_services:3.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.2.1 | cpe:2.3:a:mozilla:network_security_services:3.2.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.3 | cpe:2.3:a:mozilla:network_security_services:3.3:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.3.1 | cpe:2.3:a:mozilla:network_security_services:3.3.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.3.2 | cpe:2.3:a:mozilla:network_security_services:3.3.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.4 | cpe:2.3:a:mozilla:network_security_services:3.4:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.4.1 | cpe:2.3:a:mozilla:network_security_services:3.4.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.4.2 | cpe:2.3:a:mozilla:network_security_services:3.4.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.5 | cpe:2.3:a:mozilla:network_security_services:3.5:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.6 | cpe:2.3:a:mozilla:network_security_services:3.6:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.6.1 | cpe:2.3:a:mozilla:network_security_services:3.6.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7 | cpe:2.3:a:mozilla:network_security_services:3.7:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7.1 | cpe:2.3:a:mozilla:network_security_services:3.7.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7.2 | cpe:2.3:a:mozilla:network_security_services:3.7.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7.3 | cpe:2.3:a:mozilla:network_security_services:3.7.3:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7.5 | cpe:2.3:a:mozilla:network_security_services:3.7.5:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.7.7 | cpe:2.3:a:mozilla:network_security_services:3.7.7:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.8 | cpe:2.3:a:mozilla:network_security_services:3.8:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.9 | cpe:2.3:a:mozilla:network_security_services:3.9:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.11.2 | cpe:2.3:a:mozilla:network_security_services:3.11.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.11.3 | cpe:2.3:a:mozilla:network_security_services:3.11.3:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.11.4 | cpe:2.3:a:mozilla:network_security_services:3.11.4:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.11.5 | cpe:2.3:a:mozilla:network_security_services:3.11.5:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12 | cpe:2.3:a:mozilla:network_security_services:3.12:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.1 | cpe:2.3:a:mozilla:network_security_services:3.12.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.2 | cpe:2.3:a:mozilla:network_security_services:3.12.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.3 | cpe:2.3:a:mozilla:network_security_services:3.12.3:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.3.1 | cpe:2.3:a:mozilla:network_security_services:3.12.3.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.3.2 | cpe:2.3:a:mozilla:network_security_services:3.12.3.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.4 | cpe:2.3:a:mozilla:network_security_services:3.12.4:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.5 | cpe:2.3:a:mozilla:network_security_services:3.12.5:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.6 | cpe:2.3:a:mozilla:network_security_services:3.12.6:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.7 | cpe:2.3:a:mozilla:network_security_services:3.12.7:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.8 | cpe:2.3:a:mozilla:network_security_services:3.12.8:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.9 | cpe:2.3:a:mozilla:network_security_services:3.12.9:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.10 | cpe:2.3:a:mozilla:network_security_services:3.12.10:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.12.11 | cpe:2.3:a:mozilla:network_security_services:3.12.11:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14 | cpe:2.3:a:mozilla:network_security_services:3.14:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14.1 | cpe:2.3:a:mozilla:network_security_services:3.14.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14.2 | cpe:2.3:a:mozilla:network_security_services:3.14.2:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14.3 | cpe:2.3:a:mozilla:network_security_services:3.14.3:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14.4 | cpe:2.3:a:mozilla:network_security_services:3.14.4:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.14.5 | cpe:2.3:a:mozilla:network_security_services:3.14.5:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.15 | cpe:2.3:a:mozilla:network_security_services:3.15:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.15.1 | cpe:2.3:a:mozilla:network_security_services:3.15.1:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.15.2 | cpe:2.3:a:mozilla:network_security_services:3.15.2:*:*:*:*:*:*:* |