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.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-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 lookupExecution 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 lookupCVE-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- 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
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H0.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.7MediumVector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20200924 Cisco IOS XE Software for Cisco ASR 900 Series Route Switch Processor 3 Arbitrary Code Execution VulnerabilitiesCVE reference · vendor-advisory, x_refsource_CISCO
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
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.
