Trend Micro Apex One (On-Premise) Directory Traversal
CVE-2026-34926 is a medium-severity relative path traversal vulnerability in TrendAI Apex One from Trend Micro, with a CVSS 3.1 base score of 6.7 out of 10. It can be exploited with local access to the system by an attacker with administrator privileges, without any action from a user. The record lists version 14.0.0.17079 as the first without the flaw, so updating TrendAI Apex One to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on May 21, 2026, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update TrendAI Apex One to 14.0.0.17079 or a later version.
- Update TrendAI Apex One as a Service to 14.0.20731 or a later version.
- Update Apex One to 14.0.0.17079 or 14.0.20731, whichever matches your release line, or a later version.
- CISA's 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.
- Read the advisory on success.trendmicro.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Trend Micro | TrendAI Apex One | 2019 (14.0) up to, but not including, 14.0.0.17079 | 14.0.0.17079 |
| Trend Micro | TrendAI Apex One as a Service | SaaS up to, but not including, 14.0.20731 | 14.0.20731 |
| Trend Micro | Apex One | before 14.0.0.17079; before 14.0.20731 | 14.0.0.17079, 14.0.20731 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:L. Scored by CNA (trendmicro.com).
Official description
A directory traversal vulnerability in the Apex One (on-premise) server could allow a pre-authenticated local attacker to modify a key table on the server to inject malicious code to deploy to agents on affected installations. This vulnerability is only exploitable on the on-premise version of Apex One and a potential attacker must have access to the Apex One Server and already obtained administrative credentials to the server via some other method to exploit this vulnerability.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Relative Path Traversal
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as.. that can resolve to a location that is outside of that directory.
How developers prevent this class of flaw
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
- Deadline for US federal agencies to remediate, set by CISA.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- jvn.jp/en/vu/JVNVU90583059/Third Party Advisory
- jpcert.or.jp/english/at/2026/at260014.htmlThird Party Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34926Third Party Advisory, US Government Resource
Other vulnerabilities in TrendAI Apex One
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Recent Relative Path Traversal vulnerabilities
- 7.2 High severity
- 9.3 Critical severity
- 7.5 High severity
- 9.4 Critical severity
- 9.1 Critical severity
- 8.6 High severity
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