CVE-2021-1520 json
Cisco RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Routers Local Privilege Escalation Vulnerability
published 2021-05-06 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6987
- cvss
- 6.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
A vulnerability in the internal message processing of Cisco RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Routers could allow an authenticated, local attacker to run arbitrary commands with root privileges on the underlying operating system (OS). This vulnerability exists because an internal messaging service does not properly sanitize input. An attacker could exploit this vulnerability by first authenticating to the device and then sending a crafted request to the internal service. A successful exploit could allow the attacker to run arbitrary commands with root privileges on the underlying OS. To exploit this vulnerability, the attacker must have valid Administrator credentials for the device.
Patch / fix
- cisco rv340_firmware 1.0.03.21
- cisco rv340w_firmware 1.0.03.21
- cisco rv345_firmware 1.0.03.21
- cisco rv345p_firmware 1.0.03.21
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 y ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.7 | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 6.7 | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
Affected products
- Cisco Cisco Small Business RV Series Router Firmware
Classification
- Weakness
-
- CWE-123 Write-what-where Condition
References
Sources
- CVE List CVE-2021-1520
- NVD CVE-2021-1520
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