How severe is CVE-2018-1333?

CVE-2018-1333 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-2018-1333 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1333?

CVE-2018-1333 primarily affects Apache Http Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-1333?

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-2018-1333 published?

CVE-2018-1333 was published on 2018-06-18 and last updated on 2026-06-17.

CVE-2018-1333

CVE-2018-1333 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 17% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 17% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Apache Http Server
Published: 2018-06-18
Last modified: 2026-06-17

Description

By specially crafting HTTP/2 requests, workers would be allocated 60 seconds longer than necessary, leading to worker exhaustion and a denial of service. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.18-2.4.30,2.4.33).

Frequently asked questions

What is CVE-2018-1333?: By specially crafting HTTP/2 requests, workers would be allocated 60 seconds longer than necessary, leading to worker exhaustion and a denial of service. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.18-2.4.30,2.4.33).
How severe is CVE-2018-1333?: CVE-2018-1333 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-2018-1333 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1333?: CVE-2018-1333 primarily affects Apache Http Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-1333?: 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-2018-1333 published?: CVE-2018-1333 was published on 2018-06-18 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.4.33:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_core_services:1.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:storage_automation_store:-:*:*:*:*:*:*:*

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Browse all CWE-400 (Uncontrolled Resource Consumption) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

147.15.15.226 (ipv4-addr)
60.199.224.2 (ipv4-addr)
45.120.115.150 (ipv4-addr)
41.225.238.233 (ipv4-addr)
31.36.163.95 (ipv4-addr)
142.93.208.47 (ipv4-addr)
103.165.139.145 (ipv4-addr)
45.118.144.36 (ipv4-addr)