IRONSMITHINTEL
HIGHCVSS7.5
|
Actively Exploited
|CISA KEV|CVE-2022-27924|Auth: none — unauthenticated|Reboot: required|Manual only

Synacor Zimbra Collaboration Suite (ZCS) Command Injection Vulnerability (CVE-2022-27924)

Synacor Zimbra Collaboration Suite (ZCS) allows an attacker to inject memcache commands into a targeted instance which causes an overwrite of arbitrary cached entries.

Published Apr 21, 2022 · Updated May 29, 2026
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Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve partial data exposure, arbitrary modification of data. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2022-08-25 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Software Vulnerability (CWE-74) (CWE-74) vulnerability in Synacor Zimbra Collaboration Suite (ZCS). Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to inject arbitrary memcache commands into a targeted instance. These memcache commands becomes unescaped, causing an overwrite of arbitrary cached entries. Exploitation requires remote network access, low attack complexity, no authentication required, and no user interaction required.

📧

Phishing link

→

🖼

Malicious file

🔓

Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security
●Running zimbra collaboration suite: 8.8.15, 9.0.0
Real-world incidentsWhat we've seen

CISA confirms this CVE has been used in known ransomware campaigns. Added to the KEV catalog on 2022-08-04; federal agencies required to remediate by 2022-08-25.

How to patch

Get the fix

Apply the fixed package from your vendor. The advisory lists affected versions and the exact fixed build.

↗ Vendor advisory

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply updates per vendor instructions.

References

    1
    Vendor advisory: https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P24.1#Security_Fixes
    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2022-27924
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-27924
PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References

↗ CVE-2022-27924↗ Advisory

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