CVE-2026-34926
Trend Micro Apex One (On-Premise) Directory Traversal Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 4 June 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 6.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:L
- EPSS
- 13.42% probability · 96th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 21 May 2026 · due 4 June 2026
- Weakness
- CWE-23
- Affected
- trendmicro/apex one
- Source
- security@trendmicro.com
EPSS moved from 0.5% on 24 September 2026 to 13.4% on 27 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://success.trendmicro.com/en-US/solution/KA-0023430 ; https://nvd.nist.gov/vuln/detail/CVE-2026-34926
References
- https://jvn.jp/en/vu/JVNVU90583059/Third Party Advisory
- https://success.trendmicro.com/en-US/solution/KA-0023430Vendor Advisory
- https://success.trendmicro.com/ja-JP/solution/KA-0022974Vendor Advisory
- https://www.jpcert.or.jp/english/at/2026/at260014.htmlThird Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34926Third Party Advisory, US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.