CVE-2019-15988
mediumpriority · track · 21EPSS 0.010 · 63 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting the URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Email Security Appliance (ESA)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
- cisco email security appliance firmware≤ 12.5.0nvdUScpe:2.3:o:cisco:email_security_appliance_firmware:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20191120-esa-url-bypassCisco Email Security Appliance URL Filtering Bypass Vulnerability2019-11-20csaf · cisco_csafUS
A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting the URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-url-bypass ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-url-bypass"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2019-15988cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-mp3-bypasscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-url-bypasscnnvd
- https://vigilance.fr/vulnerability/Cisco-Email-Security-Appliance-privilege-escalation-via-URL-Filtering-Bypass-30927cnnvd
- https://www.auscert.org.au/bulletins/ESB-2019.4393/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-url-bypassenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191120-esa-url-bypassVendor Advisorynvd
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