Info Security Magazine28 Oct 2025
Actively Exploited WSUS Bug Added to CISA KEV List
Sysadmins are urged to patch WSUS vulnerability CVE-2025-59287 as soon as possible, with federal agencies required to update by November 14
Actively exploited vulnerability
CVE-2025-59287: Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability
Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution.
CISA KEV source
24 Oct 2025 added
14 Nov 2025 remediation due
Affected product
Microsoft · Windows
Known ransomware use: Unknown
Required action
Follow the source advisory and validate exposure in your environment.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Related Yasna coverage
Recent reporting that mentions CVE-2025-59287.
The Register28 Oct 2025
WSUS attacks hit 'multiple' orgs as Google and other infosec sleuths ring Redmond’s alarm bell
If at first you don’t succeed, patch and patch again More threat intel teams are sounding the alarm about a critical Windows Server Update Services (WSUS) remote code execution vulnerability, tracked as CVE-2025-59287 and now under active exploitation, just days after Microsoft pushed an emergency patch and the US Cybersecurity and Infrastructure Security Agency added the bug to its Known Exploited Vulnerabilities catalog.…
Dark Reading25 Oct 2025
Microsoft Issues Emergency Patch for Critical Windows Server Bug
Microsoft initially fixed CVE-2025-59287 in the WSUS update mechanism in the October 2025 Patch Tuesday release, but the company has now issued a second, out-of-band update for the flaw, which is under attack in the wild.