CVE-2015-1635

Exp

HTTP.sys in Microsoft Windows 7 SP1, Windows Server 2008 R2 SP1, Windows 8, Windows 8.1, and Windows Server 2012 Gold and R2 allows remote attackers to execute arbitrary code via crafted HTTP requests, aka "HTTP.sys Remote Code Execution Vulnerability."

Published: 2015-04-14 Last update: 2026-04-22 Assigner: [email protected] Source: [email protected]

NVD Status：Analyzed，CVE State: published

View at NVD, CVE.org, EUVD

Threat Intelligence & Risk Assessment for CVE-2015-1635

KEV EPSS CVSS CWE Exploit-DB Affected

Conclusion & alert: CVE-2015-1635 is rated Critical Active Threat (99.1/100): CVSS Critical severity, with high exploitation likelihood (EPSS 94.31%, 100th percentile). Core evidence: CISA KEV confirms active exploitation (added 2022-02-10) affecting Microsoft / HTTP.sys. a weakness (CWE-94) Unauthenticated remote administrative access may be possible. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2015-1635

Name: Microsoft HTTP.sys Remote Code Execution Vulnerability · CISA KEV detail

Exploit added: 2022-02-10

Action due: 2022-08-10

Required action: Apply updates per vendor instructions.

Public exploit references (Exploit-DB) for CVE-2015-1635

EDB-ID	Source	Kind	Published	Link
36776	exploit_db	edb	2015-04-16	Exploit-DB ↗
36773	exploit_db	edb	2015-04-15	Exploit-DB ↗
—	nvd_ref	exploit_tag		Exploit-DB ↗
—	nvd_ref	exploit_tag		Exploit-DB ↗
—	nvd_ref	exploit_tag		Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2015-1635

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-12-19	94.42%	94.31%	-0.10%
2	2025-12-18	94.31%	94.42%	+0.10%
3	2025-11-24	—	94.31%	—

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2015-1635

CVSS metrics for this CVE.

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
9.8	3.1	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	5.9	134c704f-9b21-4f2e-91b3-4a467353bcc0
10.0	2.0	HIGH	`AV:N/AC:L/Au:N/C:C/I:C/A:C` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:C) Complete confidentiality impact. Integrity impact (I:C) Complete integrity impact. Availability impact (A:C) Complete availability impact.	10.0	10.0	[email protected]

Weakness enumeration for CVE-2015-1635

CWE-94 MITRE ↗

Affected software / configurations for CVE-2015-1635

Vendor	Product	Version	Raw CPE
microsoft	windows_7	—	cpe:2.3:o:microsoft:windows_7:-:sp1::::::
microsoft	windows_8	—	cpe:2.3:o:microsoft:windows_8:-:::::::*
microsoft	windows_8.1	—	cpe:2.3:o:microsoft:windows_8.1:-:::::::*
microsoft	windows_server_2008	r2	cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:::::itanium:*
microsoft	windows_server_2008	r2	cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:::::x64:*
microsoft	windows_server_2012	—	cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
microsoft	windows_server_2012	r2	cpe:2.3:o:microsoft:windows_server_2012:r2:::::::*

References for CVE-2015-1635

URL	Tags
http://packetstormsecurity.com/files/131463/Microsoft-Windows-HTTP.sys-Proof-Of-Concept.html	Exploit Third Party Advisory VDB Entry
http://www.osvdb.org/120629	Broken Link
http://www.securityfocus.com/bid/74013	Third Party Advisory VDB Entry Broken Link
http://www.securitytracker.com/id/1032109	Third Party Advisory VDB Entry Broken Link
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2015/ms15-034	Patch Vendor Advisory
https://www.exploit-db.com/exploits/36773/	Exploit Third Party Advisory VDB Entry
https://www.exploit-db.com/exploits/36776/	Exploit Third Party Advisory VDB Entry
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2015-1635	US Government Resource

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