CVE-2021-1437

Cisco Aironet Access Points FlexConnect Upgrade Information Disclosure Vulnerability

HIGH

7.5

CVSS Score

Published: March 24, 2021 at 08:05 PM UTC

Updated: June 17, 2026 at 03:31 AM UTC

14 products affected across 1 vendorWireless LAN Controller SoftwareAironet Access PointCatalyst 9800 Firmware

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Severity

HIGH7.5

Exploit prediction

EPSS 2%

SSVC

No known exploit

Description

A vulnerability in the FlexConnect Upgrade feature of Cisco Aironet Series Access Points Software could allow an unauthenticated, remote attacker to obtain confidential information from an affected device. This vulnerability is due to an unrestricted Trivial File Transfer Protocol (TFTP) configuration. An attacker could exploit this vulnerability by sending a specific TFTP request to an affected device. A successful exploit could allow the attacker to download any file from the filesystem of the affected access point (AP).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Aironet Access Point · Cisco

95%

All versions

cisco-1100-integrated-services-router (environment) · cisco-aironet-1540 (environment) · cisco-aironet-1560 (environment) · cisco-aironet-1800 (environment) · cisco-aironet-2800 (environment) · cisco-aironet-3800 (environment) · cisco-aironet-4800 (environment) · cisco-catalyst-9100 (environment) · cisco-catalyst-iw6300 (environment) · cisco-esw6300 (environment)

Catalyst 9800 Firmware · Cisco

95%

17.1 ≤ v < 17.3.3

Affected range stops below 17.3.3, so it looks safe — our inference, not a vendor statement

cisco-catalyst-9800 (same device)

Wireless LAN Controller Software · Cisco

95%

8.10.112.0 ≤ v < 8.10.142.0

Affected range stops below 8.10.142.0, so it looks safe — our inference, not a vendor statement

1100 Integrated Services Router · Ciscodevice

80%

All versions