CVE-2026-66911
Zimbra is vulnerable to stored cross-site scripting (XSS) via the Content-Location MIME header in…
- Risk score
- 41/100
- CVSS
- 5.3 v4.0
- Exploit chance (30 days)
- 0.5%
- Published
- 29 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Zimbra is vulnerable to stored cross-site scripting (XSS) via the Content-Location MIME header in email attachments. Due to lack of sanitization of the Content-Location header, an attacker can set it to a javascript: URI. An unauthenticated remote attacker can send a crafted email to a victim; when the victim opens th…
- Affected
- See advisory
- Fix
- Upgrade the product to 10.1.21 or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 5.3 medium
References
Original description
Zimbra is vulnerable to stored cross-site scripting (XSS) via the Content-Location MIME header in email attachments. Due to lack of sanitization of the Content-Location header, an attacker can set it to a javascript: URI. An unauthenticated remote attacker can send a crafted email to a victim; when the victim opens the email in the Zimbra web interface and clicks the attachment name, the JavaScript payload executes in the victim's browser context. This issue was fixed in version 10.1.21
Last activity 29 Oct 2026. Patch Forecast updates every hour.