How severe is CVE-2012-4999?

CVE-2012-4999 has a CVSS 2.0 base score of 6.1, rated medium severity.

Is CVE-2012-4999 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-2012-4999?

CVE-2012-4999 primarily affects Mercurycom Mr804 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-4999?

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

When was CVE-2012-4999 published?

CVE-2012-4999 was published on 2012-09-19 and last updated on 2026-06-16.

CVE-2012-4999

CVE-2012-4999 is a medium-severity vulnerability in Mercurycom Mr804 Firmware with a CVSS 2.0 base score of 6.1. 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 6.1)
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mercurycom Mr804 Firmware
Published: 2012-09-19
Last modified: 2026-06-16

Description

Mercury MR804 Router 8.0 3.8.1 Build 101220 Rel.53006nB allows remote attackers to cause a denial of service (service hang) via a crafted string in HTTP header fields such as (1) If-Modified-Since, (2) If-None-Match, or (3) If-Unmodified-Since. NOTE: some of these details are obtained from third party information.

Frequently asked questions

What is CVE-2012-4999?: Mercury MR804 Router 8.0 3.8.1 Build 101220 Rel.53006nB allows remote attackers to cause a denial of service (service hang) via a crafted string in HTTP header fields such as (1) If-Modified-Since, (2) If-None-Match, or (3) If-Unmodified-Since. NOTE: some of these details are obtained from third party information.
How severe is CVE-2012-4999?: CVE-2012-4999 has a CVSS 2.0 base score of 6.1, rated medium severity.
Is CVE-2012-4999 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-2012-4999?: CVE-2012-4999 primarily affects Mercurycom Mr804 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-4999?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-4999 published?: CVE-2012-4999 was published on 2012-09-19 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:o:mercurycom:mr804_firmware:3.8.1:*:*:*:*:*:*:*
cpe:2.3:h:mercurycom:mr804:8.0:*:*:*:*:*:*:*

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