CVE-2026-23918: Apache HTTP Server: http2: double free and possible RCE on early reset

highCVSS 8.8CVE-2026-23918

CSIRTS triage

vendor: Apache product: Apache HTTP Server Remote code execution Memory corruption

What: A double-free vulnerability in HTTP/2 connection handling triggered by early stream reset can lead to remote code execution.
Who is affected: Deployments running Apache HTTP Server with HTTP/2 enabled processing untrusted client connections.
Urgency: Critical urgency; CVSS 8.8 and direct RCE vector demand immediate patch deployment.
Action: Update Apache HTTP Server to patched version addressing HTTP/2 double-free defect.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.8
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23918

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Elevated exploitation riskCVE-2026-2391849.7% 30-day exploitation probability — well above the norm. Schedule remediation this cycle. Riskier than 99% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-23918	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

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unknownNCSC-2026-0267 [1.00] [M/H] Vulnerabilities fixed in Apple MacOSncsc-nl
unknownApple Products Multiple Vulnerabilitieshkcert
unknownMultiple vulnerabilities in Tenable Security Center (July 21, 2026)cert-fr-avis

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