CVE-2013-5596

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.

Published: 2013-10-30 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

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.

Exploit prediction scoring system (EPSS) score for CVE-2013-5596

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)

Common vulnerability scoring system (CVSS) metrics for CVE-2013-5596

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.6 6.4 [email protected]

Weakness enumeration for CVE-2013-5596

OS Trackers for CVE-2013-5596

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

Affected software / configurations for 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:*:*:*:*:*:*

References for CVE-2013-5596

cvelogic Threat Intelligence