CVE-2026-45966 (GCVE-0-2026-45966)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:18 – Updated: 2026-05-27 12:18
VLAI
Title
apparmor: fix NULL pointer dereference in __unix_needs_revalidation
Summary
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix NULL pointer dereference in __unix_needs_revalidation When receiving file descriptors via SCM_RIGHTS, both the socket pointer and the socket's sk pointer can be NULL during socket setup or teardown, causing NULL pointer dereferences in __unix_needs_revalidation(). This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new __unix_needs_revalidation() function was added without proper NULL checks. The crash manifests as: BUG: kernel NULL pointer dereference, address: 0x0000000000000018 RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0) Call Trace: apparmor_file_receive+0x42/0x80 security_file_receive+0x2e/0x50 receive_fd+0x1d/0xf0 scm_detach_fds+0xad/0x1c0 The function dereferences sock->sk->sk_family without checking if either sock or sock->sk is NULL first. Add NULL checks for both sock and sock->sk before accessing sk_family.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6971 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 88fec3526e84123997ecebd6bb6778eb4ce779b7 , < fea017a7f6abe179decf575a2d8464c74edb3964 (git)
Affected: 88fec3526e84123997ecebd6bb6778eb4ce779b7 , < e85bc9101afc4202aa2269967ce9d3ffbecd0994 (git)
Affected: 88fec3526e84123997ecebd6bb6778eb4ce779b7 , < e2938ad00b21340c0362562dfedd7cfec0554d67 (git)
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Linux Linux Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.18.14 , ≤ 6.18.* (semver)
Unaffected: 6.19.4 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix NULL pointer dereference in __unix_needs_revalidation\n\nWhen receiving file descriptors via SCM_RIGHTS, both the socket pointer\nand the socket\u0027s sk pointer can be NULL during socket setup or teardown,\ncausing NULL pointer dereferences in __unix_needs_revalidation().\n\nThis is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new\n__unix_needs_revalidation() function was added without proper NULL checks.\n\nThe crash manifests as:\n  BUG: kernel NULL pointer dereference, address: 0x0000000000000018\n  RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0)\n  Call Trace:\n   apparmor_file_receive+0x42/0x80\n   security_file_receive+0x2e/0x50\n   receive_fd+0x1d/0xf0\n   scm_detach_fds+0xad/0x1c0\n\nThe function dereferences sock-\u003esk-\u003esk_family without checking if either\nsock or sock-\u003esk is NULL first.\n\nAdd NULL checks for both sock and sock-\u003esk before accessing sk_family."
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}



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