CVE-2018-15460

highpriority · track · 35EPSS 0.025 · 85 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
2.52% (85th) EPSS
CVSS 7.8 · high
Is it mine?
5 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper filtering of email messages that contain references to whitelisted URLs. An attacker could exploit this vulnerability by sending a malicious email message that contains a large number of whitelisted URLs. A successful exploit could allow the attacker to cause a sustained DoS condition that could force the affected device to stop scanning and forwarding email messages.

01

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
  • WorkaroundCisco Email Security Appliance (ESA)cisco_csaf

    There are two possible workarounds to address this vulnerability: 1. If the whitelist through Global URL Filtering is not needed, administrators can disable it by following these steps: On the ESA, navigate to Security Services > URL Filtering. Click on Edit Global Settings and set Use a URL whitelist to None. This disables the global whitelist. Commit the Changes. 2. If the whitelist through Global URL Filtering feature is needed, the same level of filtering can be achieved by implementing a single whitelist per Content Filter, after disabling the whitelist through Global URL Filtering, as described in step 1. Administrators can choose a specific URL Reputation range or set of URL Categories to apply the whitelist to via the Content Filter. The required steps are as follows: On the ESA, navigate to Mail Policies > Incoming Content Filters [Optionally] Create a new Content Filter by clicking Add Filter Click on the desired Content Filter > Add Action > URL Reputation > Select Custom Range Input the desired range [Alternatively] Add Action > URL Categories > Add desired Categories set Choose the desired whitelist Click OK > Submit Commit the Changes

02

cvss

Technical severity, 0–10. One row per scoring source.

8.6
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 4
v3.08.6highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.08.6highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 3.9 · impact 4
v3.08.6highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
v3.18.6highAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.17.9highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

affected products (5)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-20190109-esa-url-dosCisco Email Security Appliance URL Filtering Denial of Service Vulnerability2019-01-09csaf · cisco_csafUS

    A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper filtering of email messages that contain references to whitelisted URLs. An attacker could exploit this vulnerability by sending a malicious email message that contains a large number of whitelisted URLs. A successful exploit could allow the attacker to cause a sustained DoS condition that could force the affected device to stop scanning and forwarding email messages. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190109-esa-url-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190109-esa-url-dos"]

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

10

references (7)

External citations — patches, advisories, analysis.

scry

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