CVE-2025-54903: 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, 15:59 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 47% 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 9 Sep 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
To mitigate CVE-2025-54903, organizations should: 1) Monitor for and apply official Microsoft patches immediately upon release to address the vulnerability. 2) Implement strict email filtering and attachment scanning to block or quarantine suspicious Excel files, reducing the risk of malicious document delivery. 3) Enforce application control policies that restrict execution of untrusted macros or code within Office documents. 4) Educate users on the risks of opening unsolicited or unexpected Excel files, emphasizing caution with email attachments and links. 5) Utilize endpoint detection and response (EDR) solutions to identify and block exploitation attempts or abnormal behaviors related to Excel processes. 6) Consider disabling or limiting Office file preview features in email clients to reduce exposure. 7) Maintain regular backups and incident response plans to recover from potential compromises. These targeted actions go beyond generic advice by focusing on controlling the attack vector (malicious documents) and hardening the affected application environment.
Description
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.