How severe is CVE-2006-0884?

CVE-2006-0884 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2006-0884 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-0884?

CVE-2006-0884 primarily affects Mozilla Thunderbird. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2006-0884?

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-2006-0884 published?

CVE-2006-0884 was published on 2006-02-24 and last updated on 2026-06-16.

CVE-2006-0884

CVE-2006-0884 is a critical-severity vulnerability in Mozilla Thunderbird 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-20.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Thunderbird
Published: 2006-02-24
Last modified: 2026-06-16

Description

The WYSIWYG rendering engine ("rich mail" editor) in Mozilla Thunderbird 1.0.7 and earlier allows user-assisted attackers to bypass javascript security settings and obtain sensitive information or cause a crash via an e-mail containing a javascript URI in the SRC attribute of an IFRAME tag, which is executed when the user edits the e-mail.

Frequently asked questions

What is CVE-2006-0884?: The WYSIWYG rendering engine ("rich mail" editor) in Mozilla Thunderbird 1.0.7 and earlier allows user-assisted attackers to bypass javascript security settings and obtain sensitive information or cause a crash via an e-mail containing a javascript URI in the SRC attribute of an IFRAME tag, which is executed when the user edits the e-mail.
How severe is CVE-2006-0884?: CVE-2006-0884 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2006-0884 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-0884?: CVE-2006-0884 primarily affects Mozilla Thunderbird. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2006-0884?: 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-2006-0884 published?: CVE-2006-0884 was published on 2006-02-24 and last updated on 2026-06-16.

References

Affected products (18)

cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.4:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.5:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.6:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.7:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.7.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.7.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.7.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.8:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:0.9:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:1.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:1.0.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:1.0.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:1.0.5:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:1.0.6:*:*:*:*:*:*:*

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