CVE-2021-34696 json
Cisco ASR 900 and ASR 920 Series Aggregation Services Routers Access Control List Bypass Vulnerability
published 2021-09-23 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21346
- cvss
- 5.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 63%
- public exploits
- 0
- none known
Summary
A vulnerability in the access control list (ACL) programming of Cisco ASR 900 and ASR 920 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to incorrect programming of hardware when an ACL is configured using a method other than the configuration CLI. An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
1.00% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N |
| NVD | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
Affected products
- Cisco Cisco IOS XE Software
Classification
- Weakness
-
- CWE-284 Improper Access Control
- Technology feeds
References
Sources
- CVE List CVE-2021-34696
- NVD CVE-2021-34696
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