CVE-2008-5554

CVE-2008-5554 is a medium-severity vulnerability in Microsoft Internet Explorer with a CVSS 2.0 base score of 4.3. Its EPSS exploit-prediction score of 15% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-79.

Key facts

Description

The XSS Filter in Microsoft Internet Explorer 8.0 Beta 2 does not properly handle some HTTP headers that appear after a CRLF sequence in a URI, which allows remote attackers to bypass the XSS protection mechanism and conduct XSS or redirection attacks, as demonstrated by the (1) Location and (2) Set-Cookie HTTP headers. NOTE: the vendor has reportedly stated that the XSS Filter intentionally does not attempt to "address every conceivable XSS attack scenario."

Frequently asked questions

What is CVE-2008-5554?
The XSS Filter in Microsoft Internet Explorer 8.0 Beta 2 does not properly handle some HTTP headers that appear after a CRLF sequence in a URI, which allows remote attackers to bypass the XSS protection mechanism and conduct XSS or redirection attacks, as demonstrated by the (1) Location and (2) Set-Cookie HTTP headers. NOTE: the vendor has reportedly stated that the XSS Filter intentionally does not attempt to "address every conceivable XSS attack scenario."
How severe is CVE-2008-5554?
CVE-2008-5554 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2008-5554 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 15% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2008-5554?
CVE-2008-5554 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2008-5554?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2008-5554 published?
CVE-2008-5554 was published on 2008-12-12 and last updated on 2026-06-16.

References

Affected products (1)

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