A denial of service vulnerability exists in the HTTP 2.0 protocol stack (HTTP.sys) when HTTP.sys improperly parses specially crafted HTTP 2…

published 2018-04-12 8y ago modified 2026-06-17 4mo ago also EUVD-2018-1735

cvss: 7.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 13.7%; EPSS 13.7% chance of exploitation in 30 days, percentile 96%
public exploits: 0; none known

A denial of service vulnerability exists in the HTTP 2.0 protocol stack (HTTP.sys) when HTTP.sys improperly parses specially crafted HTTP 2.0 requests, aka "HTTP.sys Denial of Service Vulnerability." This affects Windows Server 2016, Windows 10, Windows 10 Servers.

Patch / fix

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-0956 advisory

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Exploit prediction

13.69% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	7.8	AV:N/AC:L/Au:N/C:N/I:N/A:C

Affected products

Microsoft Windows Server 2016
Microsoft Windows 10
Microsoft Windows 10 Servers

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2018-0956
patch, vendor-advisory
securityfocus.com /bid/103650
vdb-entry, third-party-advisory
securitytracker.com /id/1040661
vdb-entry, third-party-advisory

Sources

CVE List CVE-2018-0956
NVD CVE-2018-0956

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