How severe is CVE-2018-8011?

CVE-2018-8011 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-2018-8011 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 52% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8011?

CVE-2018-8011 primarily affects Apache Http Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8011?

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-2018-8011 published?

CVE-2018-8011 was published on 2018-07-18 and last updated on 2026-06-17.

CVE-2018-8011

CVE-2018-8011 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 52% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 52% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Apache Http Server
Published: 2018-07-18
Last modified: 2026-06-17

Description

By specially crafting HTTP requests, the mod_md challenge handler would dereference a NULL pointer and cause the child process to segfault. This could be used to DoS the server. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.33).

Frequently asked questions

What is CVE-2018-8011?: By specially crafting HTTP requests, the mod_md challenge handler would dereference a NULL pointer and cause the child process to segfault. This could be used to DoS the server. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.33).
How severe is CVE-2018-8011?: CVE-2018-8011 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-2018-8011 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 52% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8011?: CVE-2018-8011 primarily affects Apache Http Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8011?: 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-2018-8011 published?: CVE-2018-8011 was published on 2018-07-18 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:apache:http_server:2.4.33:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*

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Other CWE-476 (NULL Pointer Dereference) vulnerabilities

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CVE-2010-2495 — Critical (CVSS 10.0): The pppol2tp_xmit function in drivers/net/pppol2tp.c in the L2TP implementation in the Linux kernel before 2.6.34 does…
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CVE-2026-31436 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix possible wrong descriptor…

Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

1.241.64.237 (ipv4-addr)