Cisco Email Security Appliance (ESA): Improper Authentication
CVE-2022-20798 is a critical-severity improper authentication vulnerability in Cisco Email Security Appliance (ESA) from Cisco, with a CVSS 3.1 base score of 9.8 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 1.56% chance of exploitation within 30 days, higher than 76% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Email Security Appliance to 14.0.1-033 or a later version.
- Update Secure Email And Web Manager to 13.0.0-277 or 13.6.2-090 or 13.8.1-090 or 14.0.0-418, 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 | Email Security Appliance | 14.0 up to, but not including, 14.0.1-033; 7.1.5 | 14.0.1-033 |
| Cisco | Secure Email And Web Manager | 13.0 up to, but not including, 13.0.0-277; 13.6 up to, but not including, 13.6.2-090; 13.8 up to, but not including, 13.8.1-090; 14.0 up to, but not including, 14.0.0-418; 14.1 up to, but not including, 14.1.0-250 | 13.0.0-277, 13.6.2-090, 13.8.1-090, 14.0.0-418, 14.1.0-250 |
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
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | CNA (cisco.com) |
| CVSS 3.1 | 9.8 | Critical | NVD |
| CVSS 2.0 | 6.8 | Medium | NVD |
Official description
A vulnerability in the external authentication functionality of Cisco Secure Email and Web Manager, formerly known as Cisco Security Management Appliance (SMA), and Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass authentication and log in to the web management interface of an affected device. This vulnerability is due to improper authentication checks when an affected device uses Lightweight Directory Access Protocol (LDAP) for external authentication. An attacker could exploit this vulnerability by entering a specific input on the login page of the affected device. A successful exploit could allow the attacker to gain unauthorized access to the web-based management interface of the affected device.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in Cisco Email Security Appliance (ESA)
- 7.7 High severity
- 7.5 High severity
Recent Improper Authentication vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 7.8 High severity
- 8.8 High severity
- 8.6 High severity
- 7.8 High severity
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