cbcvebase.
CVE-2021-34795
published 2021-11-04

CVE-2021-34795: Multiple vulnerabilities in the web-based management interface of the Cisco Catalyst Passive Optical Network (PON) Series Switches Optical Network Terminal…

PriorityP267critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
1.75%
75.0th percentile
Multiple vulnerabilities in the web-based management interface of the Cisco Catalyst Passive Optical Network (PON) Series Switches Optical Network Terminal (ONT) could allow an unauthenticated, remote attacker to perform the following actions: Log in with a default credential if the Telnet protocol is enabled Perform command injection Modify the configuration For more information about these vulnerabilities, see the Details section of this advisory.

Affected

7 ranges
VendorProductVersion rangeFixed in
ciscocatalyst_pon_series_switches_optical_network_terminal
ciscocatalyst_pon_switch_cgp-ont-1p_firmware< 1.1.1.141.1.1.14
ciscocatalyst_pon_switch_cgp-ont-4p_firmware< 1.1.3.171.1.3.17
ciscocatalyst_pon_switch_cgp-ont-4pv_firmware< 1.1.3.171.1.3.17
ciscocatalyst_pon_switch_cgp-ont-4pvc_firmware< 1.1.3.171.1.3.17
ciscocatalyst_pon_switch_cgp-ont-4tvcw_firmware< 1.1.3.171.1.3.17
ciscocisco_catalyst_pon_series

Detection & IOCsextracted from sources · hover to see the quote

  • Detect unauthenticated login attempts to Cisco Catalyst PON ONT devices using default credentials over Telnet (when Telnet protocol is enabled)
  • Monitor the web-based management interface of Cisco Catalyst PON Series Switches ONT for unauthenticated remote access attempts, command injection payloads, and unauthorized configuration modification requests
  • ·Telnet must be enabled on the device for the default-credential login vector (CVE-2021-34795) to be exploitable; disabling Telnet reduces attack surface for that specific vector
  • ·No workarounds are available for any of the vulnerabilities in this advisory; software updates are the only remediation

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vendor_cisco10.0CRITICAL
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