The cycle collection (CC) implementation in Mozilla Firefox before 25.0, Firefox ESR 24.x before 24.1, Thunderbird before 24.1, and SeaMonkey before 2.22 does not properly determine the thread for release of an image object, which allows remote attackers to execute arbitrary code or cause a denial of service (race condition and application crash) via a large HTML document containing IMG elements, as demonstrated by the Never-Ending Reddit on reddit.com.
Conclusion & alert: CVE-2013-5596 is rated Moderate Risk (58.7/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 3.14%). Core evidence: EPSS rose +1.37% 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 | 1.77% | 3.14% | +1.37% |
| 2 | 2025-07-09 | 1.90% | 1.77% | -0.12% |
| 3 | 2025-03-30 | — | 1.90% | — |
Full EPSS history (9 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 |
|---|---|---|---|
gentoo
|
normal | CVE-2013-5596: 1 GLSA(s) (201504-01), 7 atom(s) (dev-libs/nspr, mail-client/thunderbird, …); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2013-5596 |
redhat
|
critical | — | https://access.redhat.com/security/cve/CVE-2013-5596 |
suse
|
high | CVE-2013-5596 severity important: SUSE including 59 source package names (MozillaFirefox-140.2.0-160000.1.2, MozillaFirefox-31.1.0esr-1.20, …), 75 product×package rows across 26 product lines (SUSE Linux Enterprise Desktop 12, SUSE Linux Enterprise Desktop 12 SP1, … (26 product lines)): Fixed 75. | https://www.suse.com/security/cve/CVE-2013-5596/ |
ubuntu
|
medium | CVE-2013-5596 medium priority: Ubuntu including 2 source packages (firefox, thunderbird), 12 status rows across 6 suites (lucid, precise, quantal, raring, saucy, upstream): released 10, ignored 2. | https://ubuntu.com/security/CVE-2013-5596 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| mozilla | thunderbird | <= 24.0.1 | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0 | cpe:2.3:a:mozilla:thunderbird:17.0:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.1 | cpe:2.3:a:mozilla:thunderbird:17.0.1:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.2 | cpe:2.3:a:mozilla:thunderbird:17.0.2:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.3 | cpe:2.3:a:mozilla:thunderbird:17.0.3:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.4 | cpe:2.3:a:mozilla:thunderbird:17.0.4:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.5 | cpe:2.3:a:mozilla:thunderbird:17.0.5:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.6 | cpe:2.3:a:mozilla:thunderbird:17.0.6:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.7 | cpe:2.3:a:mozilla:thunderbird:17.0.7:*:*:*:*:*:*:* |
| mozilla | thunderbird | 17.0.8 | cpe:2.3:a:mozilla:thunderbird:17.0.8:*:*:*:*:*:*:* |
| mozilla | thunderbird | 24.0 | cpe:2.3:a:mozilla:thunderbird:24.0:*:*:*:*:*:*:* |
| mozilla | thunderbird_esr | 17.0.9 | cpe:2.3:a:mozilla:thunderbird_esr:17.0.9:*:*:*:*:*:*:* |
| mozilla | firefox | 24.0 | cpe:2.3:a:mozilla:firefox:24.0:*:*:*:*:*:*:* |
| mozilla | firefox | 24.0.1 | cpe:2.3:a:mozilla:firefox:24.0.1:*:*:*:*:*:*:* |
| mozilla | firefox | 24.0.2 | cpe:2.3:a:mozilla:firefox:24.0.2:*:*:*:*:*:*:* |
| mozilla | firefox | <= 24.0 | cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* |
| mozilla | firefox | 19.0 | cpe:2.3:a:mozilla:firefox:19.0:*:*:*:*:*:*:* |
| mozilla | firefox | 19.0.1 | cpe:2.3:a:mozilla:firefox:19.0.1:*:*:*:*:*:*:* |
| mozilla | firefox | 19.0.2 | cpe:2.3:a:mozilla:firefox:19.0.2:*:*:*:*:*:*:* |
| mozilla | firefox | 20.0 | cpe:2.3:a:mozilla:firefox:20.0:*:*:*:*:*:*:* |
| mozilla | firefox | 20.0.1 | cpe:2.3:a:mozilla:firefox:20.0.1:*:*:*:*:*:*:* |
| mozilla | firefox | 21.0 | cpe:2.3:a:mozilla:firefox:21.0:*:*:*:*:*:*:* |
| mozilla | firefox | 22.0 | cpe:2.3:a:mozilla:firefox:22.0:*:*:*:*:*:*:* |
| mozilla | firefox | 23.0 | cpe:2.3:a:mozilla:firefox:23.0:*:*:*:*:*:*:* |
| mozilla | firefox | 23.0.1 | cpe:2.3:a:mozilla:firefox:23.0.1:*:*:*:*:*:*:* |
| mozilla | seamonkey | <= 2.22 | cpe:2.3:a:mozilla:seamonkey:*:beta2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:alpha_1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:alpha_2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:alpha_3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:beta_1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:beta_2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:rc1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0 | cpe:2.3:a:mozilla:seamonkey:2.0:rc2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.1 | cpe:2.3:a:mozilla:seamonkey:2.0.1:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.2 | cpe:2.3:a:mozilla:seamonkey:2.0.2:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.3 | cpe:2.3:a:mozilla:seamonkey:2.0.3:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.4 | cpe:2.3:a:mozilla:seamonkey:2.0.4:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.5 | cpe:2.3:a:mozilla:seamonkey:2.0.5:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.6 | cpe:2.3:a:mozilla:seamonkey:2.0.6:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.7 | cpe:2.3:a:mozilla:seamonkey:2.0.7:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.8 | cpe:2.3:a:mozilla:seamonkey:2.0.8:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.9 | cpe:2.3:a:mozilla:seamonkey:2.0.9:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.10 | cpe:2.3:a:mozilla:seamonkey:2.0.10:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.11 | cpe:2.3:a:mozilla:seamonkey:2.0.11:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.12 | cpe:2.3:a:mozilla:seamonkey:2.0.12:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.13 | cpe:2.3:a:mozilla:seamonkey:2.0.13:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.0.14 | cpe:2.3:a:mozilla:seamonkey:2.0.14:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:alpha1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:alpha2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:alpha3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:beta1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:beta2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:beta3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:rc1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.1 | cpe:2.3:a:mozilla:seamonkey:2.1:rc2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.10 | cpe:2.3:a:mozilla:seamonkey:2.10:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.10 | cpe:2.3:a:mozilla:seamonkey:2.10:beta1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.10 | cpe:2.3:a:mozilla:seamonkey:2.10:beta2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.10 | cpe:2.3:a:mozilla:seamonkey:2.10:beta3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.10.1 | cpe:2.3:a:mozilla:seamonkey:2.10.1:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta4:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta5:*:*:*:*:*:* |
| mozilla | seamonkey | 2.11 | cpe:2.3:a:mozilla:seamonkey:2.11:beta6:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta2:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta3:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta4:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta5:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12 | cpe:2.3:a:mozilla:seamonkey:2.12:beta6:*:*:*:*:*:* |
| mozilla | seamonkey | 2.12.1 | cpe:2.3:a:mozilla:seamonkey:2.12.1:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.13 | cpe:2.3:a:mozilla:seamonkey:2.13:*:*:*:*:*:*:* |
| mozilla | seamonkey | 2.13 | cpe:2.3:a:mozilla:seamonkey:2.13:beta1:*:*:*:*:*:* |
| mozilla | seamonkey | 2.13 | cpe:2.3:a:mozilla:seamonkey:2.13:beta2:*:*:*:*:*:* |