cbcvebase.
CVE-2022-20701
published 2022-02-10

CVE-2022-20701: Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker to do any of the following: Execute…

PriorityP181high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2022-03-17
Exploited in the wild
EPSS
9.75%
95.0th percentile
Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker to do any of the following: Execute arbitrary code Elevate privileges Execute arbitrary commands Bypass authentication and authorization protections Fetch and run unsigned software Cause denial of service (DoS) For more information about these vulnerabilities, see the Details section of this advisory.

Affected

6 ranges
VendorProductVersion rangeFixed in
ciscocisco_small_business_rv_series_router_firmware
ciscorv340_firmware<= 1.0.03.24
ciscorv340w_firmware<= 1.0.03.24
ciscorv345_firmware<= 1.0.03.24
ciscorv345p_firmware<= 1.0.03.24
ciscosmall_business_rv_series_routers

Detection & IOCsextracted from sources · hover to see the quote

path/form-file-upload
path/upload
path/tmp/websession/token/$cookie_sessionid
path/tmp/upload
path/www/cgi-bin/
filenameblockpage.cgi
filenamejsonrpc.cgi
filenameupload.cgi
ip127.0.0.1:9003
cookiesessionid
  • The /upload endpoint on Cisco RV340 series routers only checks for the existence of a session token file at /tmp/websession/token/$cookie_sessionid via nginx config — an attacker bypassing this check (CVE-2022-20705) can reach the unauthenticated file upload handler at /form-file-upload, enabling unauthenticated file upload leading to RCE as root.
  • Monitor for unexpected POST requests to /form-file-upload and /upload on Cisco RV series routers, especially from WAN interfaces if remote management is enabled, as these endpoints are the attack surface for CVE-2022-20701/20705/20707.
  • Files uploaded via the /upload endpoint are stored in /tmp/upload; monitor for unexpected files appearing in this directory on affected Cisco RV series routers as an indicator of exploitation.
  • CVE-2022-20701 is a local privilege escalation (LPE) chained with CVE-2022-20705 (Authentication Bypass) and CVE-2022-20707 (Command Injection) to achieve unauthenticated RCE as root; detections should consider the full chain, not just individual CVEs.
  • Affected firmware versions for RV340/RV345: 1.0.03.24 and earlier. Affected firmware for RV160/RV260: 1.0.01.05 and earlier. Use these version strings to identify unpatched devices in asset inventory or network scanning.
  • ·The nginx upload authentication check relies solely on the existence of a file at /tmp/websession/token/$cookie_sessionid — this is a weak file-existence check, not a cryptographic validation, making it bypassable (CVE-2022-20705).
  • ·The web UI (and thus the vulnerable /upload and /form-file-upload endpoints) is exposed on the WAN interface if remote management is enabled — organizations should verify remote management is disabled to reduce attack surface.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
vulncheck10.0CRITICAL
cisa7.8HIGH
vendor_cisco10.0CRITICAL
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