How severe is CVE-2007-0777?

CVE-2007-0777 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2007-0777 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-0777?

CVE-2007-0777 primarily affects Mozilla Firefox. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2007-0777?

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-2007-0777 published?

CVE-2007-0777 was published on 2007-02-26 and last updated on 2026-06-16.

CVE-2007-0777

CVE-2007-0777 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Mozilla Firefox
Published: 2007-02-26
Last modified: 2026-06-16

Description

The JavaScript engine in Mozilla Firefox before 1.5.0.10 and 2.x before 2.0.0.2, Thunderbird before 1.5.0.10, and SeaMonkey before 1.0.8 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via certain vectors that trigger memory corruption.

Frequently asked questions

What is CVE-2007-0777?: The JavaScript engine in Mozilla Firefox before 1.5.0.10 and 2.x before 2.0.0.2, Thunderbird before 1.5.0.10, and SeaMonkey before 1.0.8 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via certain vectors that trigger memory corruption.
How severe is CVE-2007-0777?: CVE-2007-0777 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2007-0777 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-0777?: CVE-2007-0777 primarily affects Mozilla Firefox. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2007-0777?: 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-2007-0777 published?: CVE-2007-0777 was published on 2007-02-26 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:5.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:6.06:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:6.10:*:*:*:*:*:*:*

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