{"cve":{"cve_id":"CVE-2021-22555","is_kev":true,"kev_date_added":"2025-10-06","kev_vendor_project":"Linux","kev_product":"Kernel","kev_vulnerability_name":"Linux Kernel Heap Out-of-Bounds Write Vulnerability","kev_short_description":"Linux Kernel contains a heap out-of-bounds write vulnerability that could allow an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space.","kev_required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","kev_due_date":"2025-10-27","kev_known_ransomware":false,"kev_notes":"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21 ; https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d ; https://security.netapp.com/advisory/ntap-20210805-0010/ ; https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528 ; https://nvd.nist.gov/vuln/detail/CVE-2021-22555","kev_cwes":["CWE-787"],"epss_score":0.78684,"epss_percentile":0.99585,"epss_as_of":"2026-10-15","description":"A heap out-of-bounds write affecting Linux since v2.6.19-rc1 was discovered in net/netfilter/x_tables.c. 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