How severe is CVE-2026-63718?

CVE-2026-63718 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 high, and availability none.

Is CVE-2026-63718 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-63718?

CVE-2026-63718 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-63718?

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-2026-63718 published?

CVE-2026-63718 was published on 2026-10-01 and last updated on 2026-10-06.

CVE-2026-63718

CVE-2026-63718 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-444.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Apache Http Server
Published: 2026-10-01
Last modified: 2026-10-06

Description

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') response smuggling vulnerability in Apache HTTP Server via mod_proxy_uwsgi and a crafted uwsgi response with Transfer-Encoding. This issue affects Apache HTTP Server: from 2.4.30 through 2.4.68.

Frequently asked questions

What is CVE-2026-63718?: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') response smuggling vulnerability in Apache HTTP Server via mod_proxy_uwsgi and a crafted uwsgi response with Transfer-Encoding. This issue affects Apache HTTP Server: from 2.4.30 through 2.4.68.
How severe is CVE-2026-63718?: CVE-2026-63718 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 high, and availability none.
Is CVE-2026-63718 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-63718?: CVE-2026-63718 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-63718?: 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-2026-63718 published?: CVE-2026-63718 was published on 2026-10-01 and last updated on 2026-10-06.

References

Affected products (1)

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

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