How severe is CVE-2008-4930?

CVE-2008-4930 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2008-4930 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2008-4930?

CVE-2008-4930 affects Mybb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2008-4930?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2008-4930 published?

CVE-2008-4930 was published on 2008-11-04 and last updated on 2026-06-16.

CVE-2008-4930

CVE-2008-4930 is a medium-severity vulnerability in Mybb with a CVSS 2.0 base score of 5.0. 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: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mybb
Published: 2008-11-04
Last modified: 2026-06-16

Description

MyBB (aka MyBulletinBoard) 1.4.2 does not properly handle an uploaded file with a nonstandard file type that contains HTML sequences, which allows remote attackers to cause that file to be processed as HTML by Internet Explorer's content inspection, aka "Incomplete protection against MIME-sniffing." NOTE: this could be leveraged for XSS and other attacks.

Frequently asked questions

What is CVE-2008-4930?: MyBB (aka MyBulletinBoard) 1.4.2 does not properly handle an uploaded file with a nonstandard file type that contains HTML sequences, which allows remote attackers to cause that file to be processed as HTML by Internet Explorer's content inspection, aka "Incomplete protection against MIME-sniffing." NOTE: this could be leveraged for XSS and other attacks.
How severe is CVE-2008-4930?: CVE-2008-4930 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2008-4930 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2008-4930?: CVE-2008-4930 affects Mybb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2008-4930?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2008-4930 published?: CVE-2008-4930 was published on 2008-11-04 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:mybb:mybb:1.4.2:*:*:*:*:*:*:*

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