How severe is CVE-1999-1476?

CVE-1999-1476 has a CVSS 2.0 base score of 2.1, rated low severity.

Is CVE-1999-1476 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-1476?

CVE-1999-1476 primarily affects Intel Pentium. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-1999-1476?

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

When was CVE-1999-1476 published?

CVE-1999-1476 was published on 1999-12-31 and last updated on 2026-06-16.

CVE-1999-1476

CVE-1999-1476 is a low-severity vulnerability in Intel Pentium with a CVSS 2.0 base score of 2.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Low (CVSS 2.0 base score 2.1)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Intel Pentium
Published: 1999-12-31
Last modified: 2026-06-16

Description

A bug in Intel Pentium processor (MMX and Overdrive) allows local users to cause a denial of service (hang) in Intel-based operating systems such as Windows NT and Windows 95, via an invalid instruction, aka the "Invalid Operand with Locked CMPXCHG8B Instruction" problem.

Frequently asked questions

What is CVE-1999-1476?: A bug in Intel Pentium processor (MMX and Overdrive) allows local users to cause a denial of service (hang) in Intel-based operating systems such as Windows NT and Windows 95, via an invalid instruction, aka the "Invalid Operand with Locked CMPXCHG8B Instruction" problem.
How severe is CVE-1999-1476?: CVE-1999-1476 has a CVSS 2.0 base score of 2.1, rated low severity.
Is CVE-1999-1476 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-1476?: CVE-1999-1476 primarily affects Intel Pentium. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-1999-1476?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-1999-1476 published?: CVE-1999-1476 was published on 1999-12-31 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:h:intel:pentium:*:*:mmx:*:*:*:*:*
cpe:2.3:h:intel:pentuim:*:*:overdrive:*:*:*:*:*

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