Patch testing exists to prevent broken production deployments — not to create a delay buffer. Security teams frequently report that patches are held in "testing" for weeks or months, negating the purpose of having a patch cycle. The WannaCry attack exploited EternalBlue — a vulnerability Microsoft had patched two months earlier. Most organisations that were hit had been holding the patch in their testing process. Establish a maximum testing window: 72 hours for critical patches. If a critical patch cannot complete testing in that window, deploy it with a rollback plan rather than waiting for testing to complete.
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