CVE-2015-6421

highpriority · track · 31EPSS 0.019 · 80 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.93% (80th) EPSS

CVSS 7.8 · high

Is it mine?

14 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

cifs-ao in the CIFS optimization functionality on Cisco Wide Area Application Service (WAAS) and Virtual WAAS (vWAAS) devices 5.x before 5.3.5d and 5.4 and 5.5 before 5.5.3 allows remote attackers to cause a denial of service (resource consumption and device reload) via crafted network traffic, aka Bug ID CSCus85330.

cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.06.9mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-399USprimary

affected products (14)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
cisco wide area application services= 5.1.1nvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.1.1anvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.1.1bnvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.1.1cnvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.1.1dnvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.2.1nvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.2_basenvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.1nvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.3nvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.5nvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.5anvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.5bnvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*
cisco wide area application services= 5.3.5cnvdUScpe:2.3:a:cisco:wide_area_application_services:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2016-01-27modified 2026-06-17

related (3,726)

Related entries.

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CVE-2018-0154US	high7.5OT critical	7.07% (94th)	KEV	2018-03-28
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+3721 more

references (5)

External citations — patches, advisories, analysis.

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