PatchTheCVECVE-2026-77911: Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a net
CVE-2026-77911 is a medium-severity flaw (CVSS 6.5) affecting 365 apps, microsoft 365, office 2019. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
Why this priority
- On your watchlist
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 0.9% (top 40%) |
| CISA exploited list | No |
| Weakness | CWE-125 |
| Published | 2026-09-08 |
| Last modified | 2026-10-30 |
Last updated 2026-10-30 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-77911?
365 apps: mitigate or apply the listed mitigation; microsoft 365: mitigate or apply the listed mitigation; office 2019: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2026-77911 being exploited?
CVE-2026-77911 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-77911 affect?
CVE-2026-77911 affects 365 apps, microsoft 365, office 2019. Severity is medium (CVSS 6.5). Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
How urgent is CVE-2026-77911?
Priority 43/100. On your watchlist
Software pages
Microsoft Office vulnerabilities
Related CVEs
- CVE-2023-36009 MEDIUM 5.5 MITIGATE DOWNGRADE Microsoft Word Information Disclosure Vulnerability
- CVE-2022-34717 HIGH 8.8 MITIGATE DOWNGRADE Microsoft Office Remote Code Execution Vulnerability
- CVE-2026-81396 HIGH 7.8 MITIGATE DOWNGRADE Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-78524 HIGH 8.8 MITIGATE MITIGATE Out-of-bounds write in Microsoft Office allows an unauthorized attacker to execute code over a network.
- CVE-2026-70125 HIGH 7.8 MITIGATE MITIGATE Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code locally