How severe is CVE-2006-20001?

CVE-2006-20001 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2006-20001 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-20001?

CVE-2006-20001 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2006-20001?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2006-20001 published?

CVE-2006-20001 was published on 2023-01-17 and last updated on 2026-06-16.

CVE-2006-20001

CVE-2006-20001 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 7.5. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Apache Http Server
Published: 2023-01-17
Last modified: 2026-06-16

Description

A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash. This issue affects Apache HTTP Server 2.4.54 and earlier.

Frequently asked questions

What is CVE-2006-20001?: A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash. This issue affects Apache HTTP Server 2.4.54 and earlier.
How severe is CVE-2006-20001?: CVE-2006-20001 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2006-20001 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-20001?: CVE-2006-20001 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2006-20001?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2006-20001 published?: CVE-2006-20001 was published on 2023-01-17 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

61.19.69.203 (ipv4-addr)
41.75.114.30 (ipv4-addr)
50.255.62.89 (ipv4-addr)
105.27.148.94 (ipv4-addr)
104.199.176.250 (ipv4-addr)
147.15.15.226 (ipv4-addr)
218.4.91.163 (ipv4-addr)
45.84.120.3 (ipv4-addr)