CVE-2021-1403

highpriority · track · 30OT risk · elevatedEPSS 0.006 · 50 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.62% (50th) EPSS
CVSS 7.1 · high
Is it mine?
259 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site WebSocket hijacking (CSWSH) attack and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient HTTP protections in the web UI on an affected device. An attacker could exploit this vulnerability by persuading an authenticated user of the web UI to follow a crafted link. A successful exploit could allow the attacker to corrupt memory on the affected device, forcing it to reload and causing a DoS condition.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

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

7.4
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–7.4

v2.07.1highAV:N/AC:M/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 6.9
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 4
v3.07.4highCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hsecondary · CISA US
v3.17.4highAV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 2.8 · impact 4
v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1021USprimaryCWE-345USCWE-345USCWE-345US
05

affected products (259)

Products and version ranges known to be affected.

showing 20 of 259
06

advisories (2)

Vendor and ecosystem advisories describing this.

  • cisco-sa-iosxe-cswsh-FKk9AzT5Cisco IOS XE Software Web UI Cross-Site WebSocket Hijacking Vulnerability2021-03-24csaf · cisco_csafUS

    A vulnerability in the web UI feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site WebSocket hijacking (CSWSH) attack and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient HTTP protections in the web UI on an affected device. An attacker could exploit this vulnerability by persuading an authenticated user of the web UI to follow a crafted link. A successful exploit could allow the attacker to corrupt memory on the affected device, forcing it to reload and causing a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the March 2021 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: March 2021 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74408"].

  • ICSA-21-110-02ICSA-21-110-02_Rockwell Automation Stratix Switches2021-04-20icsa · cisa_csaf_otUS

    Cisco reported these vulnerabilities to Rockwell Automation.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisa_csaf_otcisco_csafNVDCVE.orgMITRE
published 2021-03-24modified 2026-06-17
10

references (7)

External citations — patches, advisories, analysis.

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