Synacor Zimbra Collaboration Suite (ZCS) Arbitrary File Upload Vulnerability
Synacor · Zimbra Collaboration Suite (ZCS)
The flaw is an arbitrary file upload and directory traversal issue in the mboximport functionality of Synacor's Zimbra Collaboration Suite (ZCS), which extracts files from uploaded ZIP archives. An attacker who is an authenticated user holding administrator rights over the network, with no user interaction required, can upload arbitrary files to the system through this function.
Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 has mboximport functionality that receives a ZIP archive and extracts files from it. An authenticated user with administrator rights has the ability to upload arbitrary files to the system, leading to directory traversal.
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 4 months after disclosure. Public exploit code (Metasploit) appeared 19 days after disclosure.
- Disclosedday 0
- Public exploit codeMetasploit+19 days
- First seen exploitedVulnCheck KEV evidenceAdded to CISA KEVknown ransomware use; EU database agrees+4 mo
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
Patch historyEarlier and later CVEs in the same code, in date order. It shows when a fix was bypassed or incomplete and which version finally fixed it.
See the family treeA fix was bypassed or incomplete once over 4 months.
Same bug familyLinked by evidence that a fix failed or the same code was patched again. Oldest first.
- This CVECVE-2022-27925Synacor Zimbra Collaboration Suite (ZCS) Arbitrary File Upload21 Apr 2022KEV
incomplete fixHigh
Why these are linked: Link confidenceHow strong the evidence is that two CVEs are related. High: stated in the CVE text or linked in an advisory, or the same code was patched one release apart. Medium: the same code, or a version step plus a similar description. Low: similar description only.
- Stated in the CVE text
NOTE: this issue exists because of an incomplete fix for CVE-2022-27925.
- Similar weakness in the same product (machine-matched)same product + CWE + description similarity
- Stated in the CVE text
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order, 2 cited passages 2Initial AccessTA0001
Exploited via public-facing mail app upload functionality
An authenticated user with administrator rights has the ability to upload arbitrary files
CollectionTA0009
Traversal allows reading arbitrary local files
leading to directory traversal
Detection
1 rule for this CVE · 163 general rules for its techniquesRules for this CVE
1Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2022-27925 directly.General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Exploit Public-Facing ApplicationT1190149 general rules
- Arcadyan Router Exploitationscriticaltest
- Citrix ADS Exploitation CVE-2020-8193 CVE-2020-8195criticaltest
- Citrix Netscaler Attack CVE-2019-19781criticaltest
- Confluence Exploitation CVE-2019-3398criticaltest
- CVE-2010-5278 Exploitation Attemptcriticaltest
- CVE-2020-0688 Exchange Exploitation via Web Logcriticaltest
- CVE-2020-10148 SolarWinds Orion API Auth Bypasscriticaltest
- CVE-2020-5902 F5 BIG-IP Exploitation Attemptcriticaltest
Data from Local SystemT100514 general rules
- OpenCanary - SMB File Open Requesthightest
- Potential Conti Ransomware Database Dumping Activity Via SQLCmdhightest
- SQLite Chromium Profile Data DB Accesshightest
- SQLite Firefox Profile Data DB Accesshightest
- VeeamBackup Database Credentials Dump Via Sqlcmd.EXEhightest
- Script Interpreter Spawning Credential Scanner - Linuxhighexperimental
- Script Interpreter Spawning Credential Scanner - Windowshighexperimental
- Shai-Hulud NPM Package Malicious Exfiltration via Curlhighexperimental
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Not named in any threat report yetAlso mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
- 44 more on OTX