CVE-2025-53738: Microsoft 365 Apps for Enterprise · Use After Free
Affects Microsoft 365 Apps for EnterpriseSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 17:16 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
- Apply official patches from Microsoft immediately once they become available to remediate the vulnerability.
- Until patches are released, implement strict email filtering to block or quarantine suspicious attachments, especially Word documents from unknown or untrusted sources.
- Disable or restrict macros and ActiveX controls in Microsoft Word to reduce attack surface.
- Employ application whitelisting and endpoint protection solutions capable of detecting anomalous behavior related to use-after-free exploitation.
- Conduct user awareness training focused on recognizing phishing attempts and avoiding opening unsolicited or suspicious documents.
- Use network segmentation to limit lateral movement in case of compromise.
- Monitor logs and endpoint telemetry for unusual activity indicative of exploitation attempts.
- Consider deploying Microsoft Defender Exploit Guard or similar technologies that can mitigate exploitation of memory corruption vulnerabilities.
- Maintain regular backups and test restoration procedures to ensure resilience against potential ransomware or destructive payloads delivered via this vulnerability.
Description
Use after free in Microsoft Office Word allows an unauthorized attacker to execute code locally.