CVE-2013-5603

CVE-2013-5603 is a critical-severity vulnerability in Mozilla Thunderbird with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

Use-after-free vulnerability in the nsContentUtils::ContentIsHostIncludingDescendantOf function in Mozilla Firefox before 25.0, Firefox ESR 24.x before 24.1, Thunderbird before 24.1, and SeaMonkey before 2.22 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via vectors involving HTML document templates.

Frequently asked questions

What is CVE-2013-5603?
Use-after-free vulnerability in the nsContentUtils::ContentIsHostIncludingDescendantOf function in Mozilla Firefox before 25.0, Firefox ESR 24.x before 24.1, Thunderbird before 24.1, and SeaMonkey before 2.22 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via vectors involving HTML document templates.
How severe is CVE-2013-5603?
CVE-2013-5603 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2013-5603 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-5603?
CVE-2013-5603 primarily affects Mozilla Thunderbird. In total, 129 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-5603?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2013-5603 published?
CVE-2013-5603 was published on 2013-10-30 and last updated on 2026-06-16.

References

Affected products (129)

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