CVE-2020-3524

mediumpriority · track · 27OT risk · elevatedEPSS 0.003 · 21 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.29% (21st) EPSS
CVSS 6.9 · medium
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

A vulnerability in the Cisco IOS XE ROM Monitor (ROMMON) Software for Cisco 4000 Series Integrated Services Routers, Cisco ASR 920 Series Aggregation Services Routers, Cisco ASR 1000 Series Aggregation Services Routers, and Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, physical attacker to break the chain of trust and load a compromised software image on an affected device. The vulnerability is due to the presence of a debugging configuration option in the affected software. An attacker could exploit this vulnerability by connecting to an affected device through the console, forcing the device into ROMMON mode, and writing a malicious pattern using that specific option on the device. A successful exploit could allow the attacker to break the chain of trust and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco.

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.

6.9
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.06.9mediumAV:L/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 3.4 · impact 10
v3.16.8mediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 0.9 · impact 5.9
v3.06.4mediumCVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU
v3.06.4mediumCVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · psirt@cisco.com USexploitability 0.5 · impact 5.9
v3.06.4mediumCVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · Cisco PSIRT US
v3.16.4mediumAV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.16.2mediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

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

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-862USprimaryCWE-284USCWE-284US
05

affected products (8)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-rommon-secboot-7JgVLVYCCisco IOS XE ROM Monitor Software Vulnerability2020-09-24csaf · cisco_csafUS

    A vulnerability in the Cisco IOS XE ROM Monitor (ROMMON) Software for Cisco 4000 Series Integrated Services Routers, Cisco ASR 920 Series Aggregation Services Routers, Cisco ASR 1000 Series Aggregation Services Routers, and Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, physical attacker to break the chain of trust and load a compromised software image on an affected device. The vulnerability is due to the presence of a debugging configuration option in the affected software. An attacker could exploit this vulnerability by connecting to an affected device through the console, forcing the device into ROMMON mode, and writing a malicious pattern using that specific option on the device. A successful exploit could allow the attacker to break the chain of trust and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2020-09-24modified 2026-06-17
10

references (7)

External citations — patches, advisories, analysis.

scry

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