Security readout for executives and security teams
Plain-English summary
CVE-2018-10939 is a persistent cross-site scripting issue in Zimbra Web Client. Affected Zimbra Collaboration Suite 8.8 and 8.7 installations before the named Patch 4 releases could allow hostile content associated with a contact group to persist and affect webmail users.
Executive priority
Treat this as a moderate-priority legacy Zimbra remediation item. It is old and not KEV-listed in the bundle, but stored XSS in email systems can affect many users if unpatched webmail remains active.
Technical view
The CVE describes persistent XSS in Zimbra Web Client via a contact group. The fixed versions are Zimbra Collaboration Suite 8.8.8 Patch 4 and 8.7.11 Patch 4. The source bundle does not provide CVSS, CWE, exploit maturity, or detailed prerequisites.
Likely exposure
Exposure is most likely in organizations still running Zimbra Collaboration Suite 8.8 before 8.8.8 Patch 4 or 8.7 before 8.7.11 Patch 4, especially where Zimbra Web Client is used for production email.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation. This should be treated as a stored webmail XSS risk with incomplete public severity data, not as confirmed exploitation activity.
Researcher notes
The public bundle identifies the vulnerability class, affected version ranges, and fixed patch releases, but lacks CVSS, CWE, PoC status, authentication requirements, and detailed attack conditions. Avoid assuming impact beyond persistent XSS in ZWC contact groups.
Mitigation direction
- Upgrade affected Zimbra 8.8 systems to 8.8.8 Patch 4 or later.
- Upgrade affected Zimbra 8.7 systems to 8.7.11 Patch 4 or later.
- Review Zimbra Security Center and advisories for any later superseding guidance.
- Prioritize externally accessible or broadly used Zimbra Web Client deployments.
Validation and detection
- Inventory all Zimbra Collaboration Suite servers and record exact version and patch level.
- Confirm no Zimbra 8.8 server is below 8.8.8 Patch 4.
- Confirm no Zimbra 8.7 server is below 8.7.11 Patch 4.
- Check whether Zimbra Web Client is enabled and used by end users.
- Review relevant support tickets or logs for suspicious contact group behavior.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2018-10939 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://wiki.zimbra.com/wiki/Security_CenterCVE reference · x_refsource_CONFIRM
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.8/P4CVE reference · x_refsource_CONFIRM
- https://blog.zimbra.com/2018/05/new-zimbra-patches-8-8-8-patch-4-and-8-7-11-patch-4/CVE reference · x_refsource_CONFIRM
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.7.11/P4CVE reference · x_refsource_CONFIRM
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesCVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.