Security readout for executives and security teams
Plain-English summary
This vulnerability can let an unauthenticated remote attacker crash affected Cisco cBR-8 broadband routers running IOS XE. The business impact is service disruption, not data theft. It matters most where these routers support customer-facing or operational broadband services.
Executive priority
Treat this as a high-priority availability risk for broadband infrastructure. It does not indicate confidentiality compromise, but a remote crash of core service equipment can create outage, customer-impact, and operational escalation risk.
Technical view
CVE-2020-3526 is an insufficient input validation flaw in the Common Open Policy Service engine of Cisco IOS XE on Cisco cBR-8 Converged Broadband Routers. A malformed COPS message can trigger a device crash. CVSS v3.0 is 8.6, with network attack vector, low complexity, no privileges, no user interaction, and high availability impact.
Likely exposure
Exposure appears limited to Cisco cBR-8 Converged Broadband Routers running Cisco IOS XE with the vulnerable COPS engine reachable. The source bundle does not provide exact affected release numbers, CPEs, or configuration prerequisites beyond the product family.
Exploitation context
The provided sources describe remote unauthenticated crash potential, but do not state active exploitation. The CVE is not listed as KEV in the bundle. No exploit maturity, public proof-of-concept, or observed campaign evidence is provided.
Researcher notes
The key weakness is CWE-20 input validation in the COPS engine. The evidence supports denial of service only. Exact vulnerable versions, patch names, and workaround details are not included in the provided bundle, so validation should anchor on Cisco’s advisory.
Mitigation direction
- Review the Cisco advisory for affected releases, fixed software, and any official workarounds.
- Prioritize remediation for cBR-8 routers supporting production broadband or customer-facing services.
- Limit untrusted network reachability to relevant router services where operationally feasible.
- Monitor vendor guidance for any updated affected-version or workaround details.
Validation and detection
- Inventory Cisco cBR-8 Converged Broadband Routers running IOS XE.
- Compare installed IOS XE releases against Cisco advisory guidance.
- Check device logs and monitoring for unexplained crashes or reloads.
- Confirm whether COPS-related reachability exists from untrusted networks.
- Document remediation status for production and standby routers separately.
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-20: 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 lookupCVE-2020-3526 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
- High
- CVSS
- 8.6 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/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:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H3.94Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.6HighVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20200924 Cisco IOS XE Software Common Open Policy Service Engine Denial of Service VulnerabilityCVE 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.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.