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Russian hackers exploit recently patched Microsoft Office bug in attacks

BleepingComputer
Actively Exploited
CVEMicrosoftExploitVulnerability

Overview

Ukraine's Computer Emergency Response Team (CERT) has reported that Russian hackers are taking advantage of a newly patched vulnerability in Microsoft Office, identified as CVE-2026-21509. This flaw affects multiple versions of the software, which could leave users open to various cyberattacks. The exploitation of this vulnerability is concerning, especially as Microsoft Office is widely used in both personal and professional settings. Users and organizations are urged to ensure that their systems are updated with the latest security patches to mitigate the risk of being targeted. The situation underscores the need for vigilance in maintaining software security, especially with ongoing geopolitical tensions.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Microsoft Office (multiple versions)
  • Action Required: Users should apply the latest updates and patches provided by Microsoft for their respective versions of Office.
  • Timeline: Newly disclosed

Original Article Summary

Ukraine's Computer Emergency Response Team (CERT) says that Russian hackers are exploiting CVE-2026-21509, a recently patched vulnerability in multiple versions of Microsoft Office. [...]

Impact

Microsoft Office (multiple versions)

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Users should apply the latest updates and patches provided by Microsoft for their respective versions of Office. Regularly check for updates to ensure protection against this vulnerability.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Microsoft, Exploit, and 1 more.

Read Original Article

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