Security readout for executives and security teams
Plain-English summary
This Cisco wireless controller flaw can let someone nearby disrupt affected Catalyst 9000 wireless service without credentials. The attacker must be adjacent, such as within wireless range, and successful exploitation can force the device to reload, causing a denial of service.
Executive priority
Treat as high priority for wireless-dependent sites because exploitation can interrupt network availability. Urgency is highest where Catalyst 9000 wireless controllers support business-critical connectivity and 802.11r Fast Transition is enabled.
Technical view
CVE-2020-3429 is improper input handling in Cisco IOS XE Wireless Controller Software WPA2/WPA3 authentication processing. It affects Catalyst 9000 Family deployments using dot1x or PSK AKM with 802.11r BSS Fast Transition enabled. A crafted authentication packet can trigger device reload.
Likely exposure
Exposure is most likely in Cisco Catalyst 9000 wireless controller environments running IOS XE Wireless Controller Software with WPA2 or WPA3, dot1x or PSK authentication key management, and 802.11r Fast Transition enabled.
Exploitation context
The CVSS vector indicates adjacent network access, low complexity, no privileges, and no user interaction. The provided sources do not state active exploitation, and the CVE is not listed as KEV in the bundle.
Researcher notes
The bundle does not provide affected version ranges or fixed release details beyond naming Cisco IOS XE Wireless Controller Software for Catalyst 9000 Family. Avoid assuming broader Cisco IOS XE exposure without vendor confirmation.
Mitigation direction
- Review Cisco’s advisory for affected releases and fixed software guidance.
- Prioritize upgrade planning for exposed Catalyst 9000 wireless controller deployments.
- Identify WLANs using 802.11r Fast Transition with dot1x or PSK AKM.
- If business permits, disable 802.11r Fast Transition until vendor guidance is applied.
- Monitor wireless controller reloads and availability incidents for suspicious patterns.
Validation and detection
- Inventory Catalyst 9000 wireless controllers and IOS XE versions.
- Check WLAN security settings for WPA2 or WPA3 with dot1x or PSK AKM.
- Confirm whether 802.11r BSS Fast Transition is enabled.
- Compare findings with Cisco’s advisory for affected software status.
- Review device logs for unexpected reloads or authentication-related instability.
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-2020-3429 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
- 7.4 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:A/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:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H2.84Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
7.4HighVector: CVSS:3.0/AV:A/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 Wireless Controller Software for the Catalyst 9000 Family WPA 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.