The sec_asn1d_parse_leaf function in Mozilla Network Security Services (NSS) before 3.19.2.1 and 3.20.x before 3.20.1, as used in Firefox before 42.0 and Firefox ESR 38.x before 38.4 and other products, improperly restricts access to an unspecified data structure, which allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via crafted OCTET STRING data, related to a "use-after-poison" issue.
Conclusion & alert: CVE-2015-7181 is rated High Risk (65.3/100): CVSS High severity, with high exploitation likelihood (EPSS 7.51%, 94th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +2.49% 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 | 2026-06-15 | 5.02% | 7.51% | +2.49% |
| 2 | 2026-03-03 | 9.61% | 5.02% | -4.59% |
| 3 | 2026-02-21 | — | 9.61% | — |
Full EPSS history (21 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2015-7181 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-2015-7181 |
gentoo
|
normal | CVE-2015-7181: 2 GLSA(s) (201512-10, 201605-06), 6 atom(s) (dev-libs/nspr, dev-libs/nss, mail-client/thunderbird, mail-client/thunderbird-bin, www-client/firefox, www-client/firefox-bin); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2015-7181 |
redhat
|
critical | — | https://access.redhat.com/security/cve/CVE-2015-7181 |
suse
|
high | CVE-2015-7181 severity important: SUSE including 647 source package names (MozillaFirefox, MozillaFirefox-102.11.0-150200.152.87.1, …), 1015 product×package rows across 102 product lines (Image SLES12-SP5-Azure-BYOS, Image SLES12-SP5-Azure-Basic-On-Demand, … (102 product lines)): Fixed 809, Known Affected 157, Known Not Affected 49. | https://www.suse.com/security/cve/CVE-2015-7181/ |
ubuntu
|
medium | CVE-2015-7181 medium priority: Ubuntu including 3 source packages (firefox, nss, thunderbird), 15 status rows across 5 suites (precise, trusty, upstream, vivid, wily): released 15. | https://ubuntu.com/security/CVE-2015-7181 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| mozilla | network_security_services | <= 3.19.2.0 | cpe:2.3:a:mozilla:network_security_services:*:*:*:*:*:*:*:* |
| mozilla | network_security_services | 3.20.0 | cpe:2.3:a:mozilla:network_security_services:3.20.0:*:*:*:*:*:*:* |
| mozilla | firefox | <= 41.0.2 | cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* |
| mozilla | firefox | 38.0 | cpe:2.3:a:mozilla:firefox:38.0:*:*:*:*:*:*:* |
| mozilla | firefox | 38.0.1 | cpe:2.3:a:mozilla:firefox:38.0.1:*:*:*:*:*:*:* |
| mozilla | firefox | 38.0.5 | cpe:2.3:a:mozilla:firefox:38.0.5:*:*:*:*:*:*:* |
| mozilla | firefox | 38.1.0 | cpe:2.3:a:mozilla:firefox:38.1.0:*:*:*:*:*:*:* |
| mozilla | firefox | 38.1.1 | cpe:2.3:a:mozilla:firefox:38.1.1:*:*:*:*:*:*:* |
| mozilla | firefox | 38.2.0 | cpe:2.3:a:mozilla:firefox:38.2.0:*:*:*:*:*:*:* |
| mozilla | firefox | 38.2.1 | cpe:2.3:a:mozilla:firefox:38.2.1:*:*:*:*:*:*:* |
| mozilla | firefox | 38.3.0 | cpe:2.3:a:mozilla:firefox:38.3.0:*:*:*:*:*:*:* |