HOMEVULNERABILITIESCVE-2016-5303
MEDIUM

CVE-2016-5303

CWE-79Published: December 20, 2016· Updated: Jun 17, 2026

6.1
CVSS v3.1

Official Description

Cross-site scripting (XSS) vulnerability in the Horde Text Filter API in Horde Groupware and Horde Groupware Webmail Edition before 5.2.16 allows remote attackers to inject arbitrary web script or HTML via crafted data:text/html content in a form (1) action or (2) xlink attribute.

NVD Source

Technical Analysis

CVE-2016-5303 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected Vendors & Products

horde1 product(s)
groupware
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (10)

Quick Facts

CVE IDCVE-2016-5303
CVSS Score6.1 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
Affected1 vendor(s)
PublishedDec 20, 2016

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2016-5303 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.