A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification…
CVE-2022-20653 is a high-severity vulnerability in Cisco Email Security Appliance (ESA) from Cisco, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.83% chance of exploitation within 30 days, higher than 79% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Asyncos to 13.0.3 or 13.5.4.102 or 14.0.2.020, whichever matches your release line, or a later version.
- Read the advisory on tools.cisco.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cisco | Cisco Email Security Appliance (ESA) | Not specified in the record | Not stated |
| Cisco | Asyncos | before 13.0.3; 13.5.0 up to, but not including, 13.5.4.102; 14.0 up to, but not including, 14.0.2.020 | 13.0.3, 13.5.4.102, 14.0.2.020 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CNA (cisco.com) |
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 7.1 | High | NVD |
Official description
A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in DNS name resolution by the affected software. An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device. A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS condition. Continued attacks could cause the device to become completely unavailable, resulting in a persistent DoS condition.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Cisco Email Security Appliance (ESA)
- 9.8 Critical severity
- 7.7 High severity
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