Cisco Wide Area Application Services Software HTTPS Proxy Authentication Bypass Vulnerability

published 2019-06-20 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-10433

cvss: 4.0; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.8%; EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits: 0; none known

A vulnerability in the HTTPS proxy feature of Cisco Wide Area Application Services (WAAS) Software could allow an unauthenticated, remote attacker to use the Central Manager as an HTTPS proxy. The vulnerability is due to insufficient authentication of proxy connection requests. An attacker could exploit this vulnerability by sending a malicious HTTPS CONNECT message to the Central Manager. A successful exploit could allow the attacker to access public internet resources that would normally be blocked by corporate policies.

Patch / fix

fixed in 1

Cisco Cisco Wide Area Application Services (WAAS) 6.4(5.6)

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 23 mo ago (2024-11-21)

Exploit prediction

1.77% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	4.0	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD	3.0	5.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N

Affected products

Cisco Cisco Wide Area Application Services (WAAS)

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-20190619-waas-authbypass
vendor-advisory
securityfocus.com /bid/108863
vdb-entry, third-party-advisory

Sources

CVE List CVE-2019-1876
NVD CVE-2019-1876

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary