piriform CCleaner Cloud vulnerabilities

Latest piriform CCleaner Cloud CVEs

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1. CVE-2017-20201 CCleaner v5.33.6162 & CCleaner Cloud v1.07.3191 Malicious Backdoor Supply Chain Compromise

   Published 2025-10-08

   Critical·CVSS 9.3 EPSS 0.53%

   CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191 (32-bit builds) contained a malicious pre-entry-point loader that diverts execution from __scrt_common_main_seh into a custom loader. That loader decodes an embedded blob into shellcode, allocates executable heap memory, resolves...

Sources: CVE.org, NVD, CISA KEV, FIRST EPSS, OSV and public exploit-reference metadata. Product matching comes from the published CVE records. A proof-of-concept means public code exists; it is not evidence of exploitation.