How severe is CVE-2026-73636?

CVE-2026-73636 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-73636 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-73636?

CVE-2026-73636 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-73636?

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-2026-73636 published?

CVE-2026-73636 was published on 2026-10-01 and last updated on 2026-10-05.

CVE-2026-73636

CVE-2026-73636 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 8.1. 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-294.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-294
Affected product: Apache Http Server
Published: 2026-10-01
Last modified: 2026-10-05

Description

Authentication bypass by capture-replay in mod_auth_digest in Apache Software Foundation Apache HTTP Server 2.4.x on all platforms allows a man-in-the-middle (MITM) attacker to replay captured digest authentication credentials via crafted requests that trigger garbage collection of the client's shared memory entry when AuthDigestNonceLifetime is set to 0. Users are recommended to upgrade to version 2.4.69, which fixes this issue.

Frequently asked questions

What is CVE-2026-73636?: Authentication bypass by capture-replay in mod_auth_digest in Apache Software Foundation Apache HTTP Server 2.4.x on all platforms allows a man-in-the-middle (MITM) attacker to replay captured digest authentication credentials via crafted requests that trigger garbage collection of the client's shared memory entry when AuthDigestNonceLifetime is set to 0. Users are recommended to upgrade to version 2.4.69, which fixes this issue.
How severe is CVE-2026-73636?: CVE-2026-73636 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-73636 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-73636?: CVE-2026-73636 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-73636?: 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-2026-73636 published?: CVE-2026-73636 was published on 2026-10-01 and last updated on 2026-10-05.

References

Affected products (1)

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

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