CVE-2025-27915

mediumpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.041 · 91 %ileEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV

Likely / severe?

4.06% (91st) EPSS

CVSS 5.4 · medium

Is it mine?

6 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2025-10-07remediate by 2025-10-28

required action Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

EPSS · scored 2026-10-24

Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability

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.

cvss

Technical severity, 0–10. One row per scoring source.

5.4

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.4mediumAV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · ENISA EU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondaryexploitability 2.3 · impact 2.7

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:Hsecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USCWE-79US

affected products (6)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Zimbra Inc. Zimbra Collaboration Suite10.0.0 → 10.0.13fstec_bduRU
Zimbra Inc. Zimbra Collaboration Suite10.1.0 → 10.1.5fstec_bduRU
synacor zimbra collaboration suite10.0.0 → 10.0.13nvdUScpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
synacor zimbra collaboration suite10.1.0 → 10.1.5nvdUScpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
synacor zimbra collaboration suite= 9.0.0nvdUScpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2025-03-12modified 2026-06-17

references (14)

External citations — patches, advisories, analysis.

scry

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