CVE-2021-1334: Cisco Small Business RV Series Routers Management Interface Remote Command Execution and Denial of Service Vulnerabilities
Telemetry drift only. No threshold crossed and no authority ruling changed.
CVE record, CISA KEV and EPSS as of 2026-10-18.
CVEs like this one computed, by meaning
What to do now held facts and links
- No fix version is held. The CNA's first reference is the place to look: tools.cisco.com
- Record your decision, dated and frozen with today's evidence: patch by a date · mitigated by a compensating control · deferred · accepted the risk · not affected
- Check your version against the ranges this record publishes.
What it is stated by the CNA
Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly. These vulnerabilities are due to improper validation of user-supplied input in the web-based management interface. An attacker could exploit these vulnerabilities by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system or cause the device to reload, resulting in a denial of service (DoS) condition. To exploit these vulnerabilities, an attacker would need to have valid administrator credentials on the affected device.
- weakness
- CWE-121
- affected
- Cisco Small Business RV Series Router Firmware
- published ranges
- cisco rv016 multi-wan vpn router firmware <= 4.2.3.14; cisco rv042 dual wan vpn router firmware <= 4.2.3.14; cisco rv042g dual gigabit wan vpn router firmware <= 4.2.3.14; cisco rv082 dual wan vpn router firmware <= 4.2.3.14; and 2 more on the CVE page
- fixed in
- No fix version in held sources.
- severity
- 7.2 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- assigned by
- cisco
- published
- 2021-02-04
check us tools.cisco.com
Exploit code held, dated
- exploit code
- None held in the PoC-in-GitHub feed. A public repository changes this brief.
What moved held, dated
| date | EPSS | event |
|---|---|---|
| 14 Apr 2021 | 0.01213 | |
| 6 Jan 2022 | 0.0522 | |
| 4 Feb 2022 | 0.15362 | crossed 0.10 |
| 1 Apr 2022 | 0.01156 | crossed 0.10 |
| 7 Mar 2023 | 0.00157 | scoring model v2023.03.01 |
| 29 Apr 2023 | 0.00221 | |
| 22 Oct 2024 | 0.00212 | |
| 24 Nov 2024 | 0.00241 | |
| 17 Mar 2025 | 0.00152 | scoring model v2025.03.14 |
| 19 Mar 2025 | 0.00309 | |
| 25 Mar 2025 | 0.00505 | |
| 29 Mar 2025 | 0.01459 | |
| 30 Mar 2025 | 0.00505 | |
| 6 Feb 2026 | 0.00435 | |
| 15 Jun 2026 | 0.02753 | scoring model v2026.06.15 |
15 observations held. A step marked with a scoring model moved because the measurement was replaced, not because the vulnerability changed.
Outside the record researched, cited
This section reads the record's references and adds cited findings from outside it. It needs an account. Everything above is held facts and is complete without it.
What would change this brief held, dated
- CISA KEV
- Not listed in the catalogue we hold. A listing changes this brief.
- exploit probability
- 0.03 on 2026-06-15 (FIRST's EPSS, a probability and not evidence of exploitation). Next band line: 10% (0.10). Crossing a line changes this brief.
- fix
- No fix version is held. One published by the CNA or OSV changes this brief.
How to check this
Every value above is held with two dates: when it was true upstream (as_of) and when we recorded it (tx_from). Re-derive the exploit probability as it stood on any date:
SELECT value, source, source_version, as_of, tx_from
FROM volatile_valid_as_of('CVE-2021-1334', '2026-10-29T23:59:59.999999Z', now());