Vulnerability Report

CVE-2025-27915

CISA KEV Active

Title: Synacor Zimbra Collaboration Suite Cross-Site Scripting (XSS)

XSS

Proof Of Concept

No public PoC currently indexed for CVE-2025-27915.

CWE Category CWE-79
Published Date Mar 12, 2025
Modified Date Nov 04, 2025
Exploit Status Not Found
Score 5.4 CVSS v3.1
Exploit Probability (EPSS)
26.05%

Vulnerability Summary

CVE-2025-27915: An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient sanitization of HTML content in ICS files. When a user views an e-mail message containing a malicious ICS entry, its embedded JavaScript executes via an ontoggle event inside a <details> tag. This allows an attacker to run arbitrary JavaScript within the victim's session, potentially leading to unauthorized actions such as setting e-mail filters to redirect messages to an attacker-controlled address. As a result, an attacker can perform unauthorized actions on the victim's account, including e-mail redirection and data exfiltration.

Impacted Vendors

S
synacor 1
Z
zimbra 1

Reference Links

https://wiki.zimbra.com/wiki/Security_Center https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.13#Security_Fixes https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.5#Security_Fixes https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P44#Security_Fixes https://strikeready.com/blog/0day-ics-attack-in-the-wild/ https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-27915
CVSS v3.1
Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0
Severity MEDIUM
5.4
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
REQUIRED
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
CHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2025-27915 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

MODIFIED

Vulnerability data updated via NVD.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction REQUIRED
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected Stack

No specific products linked.