CVE-2021-1539

mediumpriority · track · 35OT risk · elevatedEPSS 0.011 · 65 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.09% (65th) EPSS

CVSS 6.5 · medium

Is it mine?

9 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisco_csaf · nvd

EPSS · scored 2026-10-27

Multiple vulnerabilities in the authorization process of Cisco ASR 5000 Series Software (StarOS) could allow an authenticated, remote attacker to bypass authorization and execute a subset of CLI commands 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 ASR 5000 Series 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.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–8.8

v2.06.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8 · impact 6.4

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · psirt@cisco.com USexploitability 2.8 · impact 5.2

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · Cisco PSIRT US

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-863US

affected products (9)

Products and version ranges known to be affected.

Cisco Cisco ASR 5000 Series Softwareall versionscisco_csafUS
Cisco Cisco ASR 5000 Series Software≤ n/aenisa_euvdEU
cisco staros< 21.16.9nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco staros21.17.0 → 21.17.10nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco staros21.18.0 → 21.18.16nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco staros21.19.0 → 21.19.11nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco staros21.19.n → 21.19.n7nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco staros21.20.0 → 21.20.8nvdUScpe:2.3:o:cisco:staros:*:*:*:*:*:*:*:*
cisco virtualized packet coreall versionsnvdUScpe:2.3:a:cisco:virtualized_packet_core:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-asr5k-autho-bypass-mJDF5S7nCisco ASR 5000 Series Software Authorization Bypass Vulnerabilities2021-06-02csaf · cisco_csafUS
Multiple vulnerabilities in the authorization process of Cisco ASR 5000 Series Software (StarOS) could allow an authenticated, remote attacker to bypass authorization and execute a subset of CLI commands 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 (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisco_csaf nvd NVD CVE.org MITRE

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

references (7)

External citations — patches, advisories, analysis.

scry

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