CVE-2019-1886

mediumpriority · track · 34EPSS 0.013 · 71 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.35% (71st) EPSS

CVSS 5 · medium

Is it mine?

9 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 HTTPS decryption feature of Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Secure Sockets Layer (SSL) server certificates. An attacker could exploit this vulnerability by installing a malformed certificate in a web server and sending a request to it through the Cisco WSA. A successful exploit could allow the attacker to cause an unexpected restart of the proxy process on an affected device.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedCisco Web Security Appliance (WSA)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.

8.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–8.6

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

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)

ssvc

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

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

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimaryCWE-20USCWE-20US

affected products (9)

Products and version ranges known to be affected.

Cisco Cisco Web Security Appliance (WSA)all versionscisco_csafUS
Cisco Cisco Web Security Appliance (WSA)unspecified → 10.5.5-005enisa_euvdEU
Cisco Systems Inc. Cisco Web Security Appliance≤ 11.7.0-FCS-334fstec_bduRU
Cisco Systems Inc. Cisco Web Security Appliance≤ 10.5.2-072fstec_bduRU
cisco asyncos10.5 → 10.5.5-005nvdUScpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*
cisco asyncos11.5 → 11.5.2-020nvdUScpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*
cisco web security appliance= 10.5.2-072nvdUScpe:2.3:a:cisco:web_security_appliance:*:*:*:*:*:*:*:*
cisco web security appliance= 10.5.3-025nvdUScpe:2.3:a:cisco:web_security_appliance:*:*:*:*:*:*:*:*
cisco web security appliance= 11.7.0-fcs-334nvdUScpe:2.3:a:cisco:web_security_appliance:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-20190703-wsa-dosCisco Web Security Appliance HTTPS Certificate Denial of Service Vulnerability2019-07-03csaf · cisco_csafUS
A vulnerability in the HTTPS decryption feature of Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Secure Sockets Layer (SSL) server certificates. An attacker could exploit this vulnerability by installing a malformed certificate in a web server and sending a request to it through the Cisco WSA. A successful exploit could allow the attacker to cause an unexpected restart of the proxy process on an affected device. Cisco has released software updates that address this vulnerability. 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-20190703-wsa-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190703-wsa-dos"]

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisco_csaf nvd NVD CVE.org MITRE

published 2019-07-04modified 2026-06-17

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+1889 more

references (11)

External citations — patches, advisories, analysis.

scry

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