CVE-2025-53759: Microsoft 365 Apps for Enterprise · Use of Uninitialized Resource
Affects Microsoft 365 Apps for EnterpriseSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 12 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft 365 Apps for Enterprise | Affected
| Fixed in– |
AI-suggested
Until an official patch is released, organizations should implement several specific mitigations to reduce risk. First, enforce strict endpoint security policies, including application whitelisting and behavior monitoring to detect suspicious Excel activity. Educate users on the risks of opening unsolicited or unexpected Excel files, emphasizing caution with email attachments and links. Employ network segmentation and least privilege principles to limit local access to critical systems. Use advanced threat protection solutions capable of sandboxing and analyzing Office documents for malicious behavior. Monitor logs and alerts for unusual Excel process executions or code injection attempts. Disable or restrict macros and other scripting features within Excel where possible, as these can be vectors for exploitation. Once Microsoft releases a patch, prioritize immediate deployment across all affected systems. Additionally, maintain regular backups and incident response readiness to mitigate potential damage from exploitation.
Description
Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to execute code locally.