LiveActive security incident?Get immediate response
CVE Record

CVE-2020-3513: Cisco IOS XE Software for Cisco ASR 900 Series Route Switch Processor 3 Arbitrary Code Execution Vulnerabilities

Multiple vulnerabilities in the initialization routines that are executed during bootup of Cisco IOS XE Software for Cisco ASR 900 Series Aggregation Services Routers with a Route Switch Processor 3 (RSP3) installed could allow an authenticated, local attacker with high privileges to execute persistent code at bootup and break the chain of trust. These vulnerabilities are due to incorrect validations by boot scripts when specific ROM monitor (ROMMON) variables are set. An attacker could exploit these vulnerabilities by copying a specific file to the local file system of an affected device and defining specific ROMMON variables. A successful exploit could allow the attacker to run arbitrary code on the underlying operating system (OS) with root privileges. To exploit these vulnerabilities, an attacker would need to have access to the root shell on the device or have physical access to the device.

MediumCVSS 6.7Not KEV-listedUpdated
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2020-3513 affects Cisco ASR 900 Series routers using RSP3. A highly privileged insider or someone with physical access could make code run during boot and persist below normal controls. This is not a typical remote internet attack, but it matters for trusted network infrastructure.

Executive priority

Prioritize for telecom, edge routing, and service-provider environments using Cisco ASR 900 RSP3. Remediation urgency is moderate unless there is insider risk, physical exposure, or signs of administrative compromise.

Technical view

Cisco describes multiple IOS XE boot initialization flaws on ASR 900 RSP3 systems. Incorrect boot-script validation of ROMMON variables can allow persistent arbitrary code execution on the underlying OS with root privileges, breaking the device chain of trust. Exploitation requires root shell access or physical access.

Likely exposure

Exposure appears narrow: Cisco ASR 900 Series Aggregation Services Routers with Route Switch Processor 3 running IOS XE. Organizations without this hardware profile are unlikely to be affected based on the provided sources.

Exploitation context

The provided bundle does not show CISA KEV listing or public active exploitation evidence. The required attacker position is already severe: root shell access on the device or physical access.

Researcher notes

The key security boundary is boot trust, not remote reachability. Evidence is limited to the CVE record and Cisco advisory metadata in the bundle; use vendor guidance for exact affected releases and fixes.

Mitigation direction

  • Identify Cisco ASR 900 routers with RSP3 installed.
  • Check Cisco's advisory for affected and fixed IOS XE releases.
  • Restrict physical and administrative access to affected routers.
  • Review boot integrity controls and unauthorized configuration changes.
  • Treat unexpected boot persistence indicators as a high-priority incident.

Validation and detection

  • Inventory ASR 900 devices and confirm RSP3 presence.
  • Verify IOS XE versions against Cisco's advisory.
  • Review administrative access history for high-privilege misuse.
  • Inspect ROMMON settings for unexpected boot-related changes.
  • Check local device storage for unauthorized boot-time artifacts.
Prepared
Confidence
high
Sources
3

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-749: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2020-3513 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.7 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
6.7CVSS 3.1MediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H0.85.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.7Medium
CVSS 3.1 vector shape for CVE-2020-3513Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone
Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
CiscoCisco IOS XE Softwaren/aListed
Weakness

CWE details

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-749 · source CWE mapping

Exposed Dangerous Method or Function

Exposed Dangerous Method or Function represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.