How severe is CVE-2026-44631?

CVE-2026-44631 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-44631 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-44631?

CVE-2026-44631 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-44631?

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

Does CVE-2026-44631 have an EU (EUVD) identifier?

Yes. CVE-2026-44631 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35095.

When was CVE-2026-44631 published?

CVE-2026-44631 was published on 2026-06-08 and last updated on 2026-06-17.

CVE-2026-44631

CVE-2026-44631 is a critical-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 9.8. 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-124.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35095
Weakness: CWE-124
Affected product: Apache Http Server
Published: 2026-06-08
Last modified: 2026-06-17

Description

Buffer Underwrite vulnerability in Apache HTTP Server on crafted regular expressions in the configuration. This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.

Frequently asked questions

What is CVE-2026-44631?: Buffer Underwrite vulnerability in Apache HTTP Server on crafted regular expressions in the configuration. This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
How severe is CVE-2026-44631?: CVE-2026-44631 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-44631 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-44631?: CVE-2026-44631 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-44631?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-44631 have an EU (EUVD) identifier?: Yes. CVE-2026-44631 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35095.
When was CVE-2026-44631 published?: CVE-2026-44631 was published on 2026-06-08 and last updated on 2026-06-17.

References

Affected products (1)

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

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Threat intelligence

Threat-intel indicators referencing this CVE:

50.255.62.89 (ipv4-addr)
147.15.15.226 (ipv4-addr)
45.84.120.3 (ipv4-addr)
77.90.185.88 (ipv4-addr)
77.90.185.87 (ipv4-addr)
74.87.117.150 (ipv4-addr)
50.35.168.148 (ipv4-addr)
49.0.24.107 (ipv4-addr)