CVE-2022-20653
published 2022-02-17CVE-2022-20653: A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Security…
PriorityP343high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.83%
76.5th percentile
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.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | asyncos | < 13.0.3 | 13.0.3 |
| cisco | asyncos | >= 13.5.0 < 13.5.4.102 | 13.5.4.102 |
| cisco | asyncos | >= 14.0 < 14.0.2.020 | 14.0.2.020 |
| cisco | cisco_email_security_appliance | — | — |
| cisco | email_security_appliance | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.07.1HIGHAV:N/AC:M/Au:N/C:N/I:N/A:C
vendor_cisco7.5HIGH
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Cisco
Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
vendor_cisco·2022-02-16·CVSS 7.5
CVE-2022-20653 [HIGH] CWE-399 Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
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 r
Cisco
Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
vendor_cisco·CVSS 3.1
CVE-2022-20653 Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
CVE-2022-20653: Cisco Email Security Appliance DNS Verification Denial of Service Vulnerability
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 unti
GHSA
GHSA-p3pv-g3c9-4qf8: A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Securi
ghsa_unreviewed·2022-02-18
CVE-2022-20653 [HIGH] GHSA-p3pv-g3c9-4qf8: A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Securi
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
No detection rules found.
No public exploits indexed.
Bleepingcomputer
New Cisco DoS flaw requires manual reboot to revive devices
blogs_bleepingcomputer·2026-05-06·CVSS 9.9
CVE-2026-20188 [CRITICAL] New Cisco DoS flaw requires manual reboot to revive devices
## New Cisco DoS flaw requires manual reboot to revive devices
## Sergiu Gatlan
Cisco released security updates to fix a Crosswork Network Controller (CNC) and Network Services Orchestrator (NSO) denial-of-service (DoS) vulnerability that requires manually rebooting targeted systems for recovery.
Large enterprises and service providers leverage the CNC software suite to simplify multivendor network management and operations handling with automation, while the NSO orchestration platform helps them manage network devices and resources.
Tracked as CVE-2026-20188 , this high-severity security flaw stems from inadequate rate limiting on incoming network connections and can be exploited remotely by unauthenticated threat actors to crash unpatched Cisco CNC and Cisco NSO systems through low-c
Checkpoint
21st February– Threat Intelligence Report
blogs_checkpoint·2022-02-21·CVSS 9.8
CVE-2018-13379 [CRITICAL] 21st February– Threat Intelligence Report
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2022-02-17
Published