CVE-2021-1288

highpriority · track · 31EPSS 0.020 · 80 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.95% (80th) EPSS

CVSS 7.8 · high

Is it mine?

8 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

Multiple vulnerabilities in the ingress packet processing function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

remediations

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

A vendor fix is available.

FixedCisco IOS XR Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com

cvss

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

8.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6

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

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.18.6highAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 3.9 · impact 4

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-399USCWE-399US

affected products (8)

Products and version ranges known to be affected.

Cisco Cisco IOS XR Softwareall versionscisco_csafUS
Cisco Cisco IOS XR Software≤ n/aenisa_euvdEU
Cisco Systems Inc. Cisco IOS XR5.0.0 → 5.2.6fstec_bduRU
Cisco Systems Inc. Cisco IOS XR5.3.0 → 5.3.4fstec_bduRU
Cisco Systems Inc. Cisco IOS XR6.0.0 → 6.0.2fstec_bduRU
cisco ios xr5.0.0 → 5.2.6nvdUScpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*
cisco ios xr5.3.0 → 5.3.4nvdUScpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*
cisco ios xr6.0.0 → 6.0.2nvdUScpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-iosxr-dos-WwDdghs2Cisco IOS XR Software Enf Broker Denial of Service Vulnerability2021-02-03csaf · cisco_csafUS
Multiple vulnerabilities in the ingress packet processing function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details ["#details"] section of this advisory. Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisco_csaf nvd NVD CVE.org MITRE

published 2021-02-04modified 2026-06-17

references (5)

External citations — patches, advisories, analysis.

scry

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