CVE-2015-8766

Symphony CMS XSS Vulnerabilities

6.1 MediumFix available

Multiple cross-site scripting (XSS) vulnerabilities in content/content.systempreferences.php in Symphony CMS before 2.6.4 allow remote attackers to inject arbitrary web script or HTML via the (1) email_sendmail[from_name], (2) email_sendmail[from_address], (3) email_smtp[from_name], (4) email_smtp[from_address], (5) email_smtp[host], (6) email_smtp[port], (7) jit_image_manipulation[trusted_external_sites], or (8) maintenance_mode[ip_whitelist] parameters to system/preferences.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required

What an attacker can affect

Confidentiality: Low
Integrity: Low
Availability: None

Exploit likelihood

1.77%Up 0.6 points since Feb 4, 2022

What each source reports

NVD Score used 6.1

Record: CVE-2015-8766
CVSS 3.0: 6.1 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS 2.0: 4.3 MediumAV:N/AC:M/Au:N/C:N/I:P/A:N
Weakness: CWE-79
Updated: 2026-11-02

CVE List No score

Record: CVE-2015-8766
Updated: 2026-11-02

EUVDEUVD-2022-2352 No score

Record: EUVD-2022-2352
Updated: 2026-11-03

GitHub AdvisoriesGHSA-4c5w-qqfg-grf3 6.1

Symphony CMS XSS Vulnerabilities

Multiple cross-site scripting (XSS) vulnerabilities in content/content.systempreferences.php in Symphony CMS before 2.6.4 allow remote attackers to inject arbitrary web script or HTML via the (1) email_sendmail[from_name], (2) email_sendmail[from_address], (3) email_smtp[from_name], (4) email_smtp[from_address], (5) email_smtp[host], (6) email_smtp[port], (7) jit_image_manipulation[trusted_external_sites], or (8) maintenance_mode[ip_whitelist] parameters to system/preferences.

Record: GHSA-4c5w-qqfg-grf3
CVSS 3.0: 6.1 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness: CWE-79
Updated: 2026-11-02

OSVGHSA-4c5w-qqfg-grf3 6.1

Symphony CMS XSS Vulnerabilities

Record: GHSA-4c5w-qqfg-grf3
CVSS 3.0: 6.1 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness: CWE-79
Updated: 2026-11-02

Affected products

getsymphony symphony

Affected packages

Affected packages
Package	Affected	Fixed
`symphonycms/symphony-2` Packagist	before 2.6.4	2.6.4
`symphonycms/symphony-2` Packagist	before 2.6.4, plus listed versions 2.6.02.6.0-beta.22.6.0-rc.12.6.12.6.22.6.3	2.6.4

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2015-8766 is a medium vulnerability (CVSS 6.1) in Getsymphony Symphony, published January 8, 2016. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.77%, the 78th percentile. Fixed in symphonycms/symphony-2 2.6.4.