Evidence dossier

CVE-2015-1635

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…

Exploited in the wild (CISA KEV since Feb 10, 2022). NVD reports CVSS 2.0 10.0. EPSS estimates 100.0% exploit likelihood as of Jul 18, 2026.

90.091.0Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

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."

State
PUBLISHED
Published
Apr 14, 2015
Updated
Oct 22, 2025
Evidence coverage
98%

Evidence chronology

What was known when

Download this view's receipt →
  1. Source dateSource date omittedFirst observed by CASCA
    CISA-ADP

    Record text: CISA ADP Vulnrichment

    Inspect raw assertion
    Field
    container
    Value
    CISA ADP Vulnrichment
    Original evidence ↗
  2. Source dateSource date omittedFirst observed by CASCA
    CVE Program

    Record text: CVE Program Container

    Inspect raw assertion
    Field
    container
    Value
    CVE Program Container
    Original evidence ↗
  3. Source dateSource date omittedFirst observed by CASCA
    microsoft

    Record text: 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."

    Inspect raw assertion
    Field
    container
    Value
    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."
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Microsoft HTTP.sys Remote Code Execution Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Microsoft HTTP.sys Remote Code Execution Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 100% probability · 100th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.999990000000; percentile 0.999980000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Feb 10, 2022 · first observed Jul 19, 2026

Exploit likelihood100.00%

FIRST EPSS · score date Jul 18, 2026 · 100th percentile · first observed Jul 19, 2026

SeverityCVSS 10.0

NVD · CVSS 2.0 · first observed Jul 19, 2026 · same-version scores align in this snapshot

Evidence detail

Source limits and decisions

Why each evidence state has this value

casca-unknown-reasons-v1
Exploitation statusEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
None
Affected productsSource-reported scope

The cited source assertion is retained while canonical product linkage remains open.

Revision
casca-factor-d-obligations-v1
Cutoff
Aug 27, 2026
Resolution
Resolve identity

Source comparison

Who said what

CISA-ADPIndependent enrichment
Record text

CISA ADP Vulnrichment

Inspect raw assertion
Field
container
Value
CISA ADP Vulnrichment
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CVE ProgramDerivative copy
Record text

CVE Program Container

Inspect raw assertion
Field
container
Value
CVE Program Container
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
microsoftOriginal assertion
Record text

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."

Inspect raw assertion
Field
container
Value
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."
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Microsoft HTTP.sys Remote Code Execution Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Microsoft HTTP.sys Remote Code Execution Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

100% probability · 100th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.999990000000; percentile 0.999980000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
7Underlying assertions
5Canonical products
7Target assertions
0Constraint assertions

Grouped from 1 configuration nodes in this exact snapshot. Visual grouping is navigational; asset exposure and root cause require cited evidence.

Identity source boundaries
  • Cpe dictionary1,775,266 records · observed through 2026-07-21T06:45:29.809Z27d65b0f-b718-4b4f-bb79-c47c68d09dfa
  • Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z955dae73-7302-438b-aee1-058d7cc5d48e

6 scope groups

microsoft · source assertedn/an/aDirect source scope
Affected: n/a
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "n/a"}]
NVD CPE · OPERATING SYSTEMmicrosoftwindows_7Vulnerable target · 1 assertions
Version not applicableCanonical identity product-f20a05098a41a238f96b56b817d0482887bb39ad40620198bbe05da10ee02ffcLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    c2b1c231-de19-4b8f-a4aa-5b3a65276e46
NVD CPE · OPERATING SYSTEMmicrosoftwindows_8Vulnerable target · 1 assertions
Version not applicableCanonical identity product-5a559e3d4b779565d6fa99223972e75a4cba4d476b27b830a78ab8eb44d5bef2Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_8:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    0d229e41-a971-4284-9657-16d78414b93f
NVD CPE · OPERATING SYSTEMmicrosoftwindows_8.1Vulnerable target · 1 assertions
Version not applicableCanonical identity product-7e46de82012029583622f69d79b86bc210b5bd25b8cb3bb4468936702b23c4b0Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    e93068db-549b-45ab-8e5c-00eb5d8b5cf8
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2008Vulnerable target · 2 assertions
Version r2Canonical identity product-217b1ab3d25f361a639824f86753d418b35aa2a816ee370bb71b5d1dd883d87aLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    af07a81d-12e5-4b1d-bff9-c8d08c32ff4f
  2. cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:itanium:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    b320a104-9037-487e-bc9a-62b4a6b49fd0
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2012Vulnerable target · 2 assertions
Version not applicable; Version r2Canonical identity product-5a80416e92fed0cddbb3d4f3840218b448dee11159824ad25a0353da566963feLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 5
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    a7df96f8-ba6a-4780-9ca3-f719b3f81074
  2. cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 6
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    db18c4ce-5917-401e-acf7-2747084fd36e

Affected-product evidence

Accepted scope and product mapping

5 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-217b1ab3d25f361a639824f86753d418b35aa2a816ee370bb71b5d1dd883d87a

Source class
Nvd cpe vulnerable target
Assertions
2
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
4bd8e9b6-a7de-4091-83ea-497462ee407891c2d3fe-adb1-4a7b-8cf4-10b522d9ac8f
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-5a559e3d4b779565d6fa99223972e75a4cba4d476b27b830a78ab8eb44d5bef2

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
aa400e52-6189-44bc-a5b4-d7596efeede8
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-5a80416e92fed0cddbb3d4f3840218b448dee11159824ad25a0353da566963fe

Source class
Nvd cpe vulnerable target
Assertions
2
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
f569d2c4-3939-40c5-b4e2-53931907e505f78761fc-6f16-4c0a-97a0-c9b202f85f33
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-7e46de82012029583622f69d79b86bc210b5bd25b8cb3bb4468936702b23c4b0

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
5d37a838-7684-4453-95b5-333c82921cf1
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-f20a05098a41a238f96b56b817d0482887bb39ad40620198bbe05da10ee02ffc

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
d9d1a915-de7a-47a2-a778-0caa0c07ec75
Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Direct cve affected
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
0c469440-b3c3-4de2-9d64-3b3aea59f042

Assessments

CVSS by origin

10.0
NVDCVSS 2.0 · role Primary · priority eligiblevalid_matchAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8
CVE Program sourceCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8
CISA-ADPCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Direct CVE/CNA normalized decisions

9.8Priority eligible

CISA-ADP

CVSS 3.1 · Secondary · Independent enrichment · rank 2

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Validation
Valid match
Recomputed
9.8
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1

Assessments are retained side by side under closed precedence. Cascade never averages CVSS.

Evidence boundaries

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; remaining scope stays source-scoped.
  • NVD-carried upstream facts remain derivative; independent corroboration requires a separately authored source.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.
  • OSV aggregation and OSV-converted NVD material are not independent corroboration.
  • Red Hat facts are vendor assertions for the exact supplied products.
  • Nonmembership and not-yet-observed states are not proof of safety.