Coverage › CVE-2025-27915
CVE-2025-27915 Unmapped
Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability
- Vendor / product
- Synacor — Zimbra Collaboration Suite (ZCS)
- Description (CISA)
- Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that 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 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.
- Added to KEV
- 2025-10-07 — after the latest CTID mapping snapshot (2025-07-28)
- Due date
- 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.
- Known ransomware use
- Unknown
- CWE
- CWE-79
- CISA notes
- https://wiki.zimbra.com/wiki/Security_Center
https://nvd.nist.gov/vuln/detail/CVE-2025-27915 - Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques
No public source states how this vulnerability is exploited in ATT&CK terms.
The only authoritative CVE → ATT&CK mapping in the open — CTID's Mappings Explorer, pinned to a KEV snapshot of 2025-07-28 and ATT&CK 16.1 — does not include CVE-2025-27915. This entry was added to KEV on 2025-10-07, after that snapshot; of the 283 entries added since, 0 have a mapping. CISA's catalogue carries no technique field. kevmap does not infer techniques from the CWE (CWE-79) — here is why — and does not guess.
This page will change state automatically if a mapping is published. What is shown above is everything CISA publishes about the entry.