{"id":"DEBIAN-CVE-2023-52443","details":"In the Linux kernel, the following vulnerability has been resolved:  apparmor: avoid crash when parsed profile name is empty  When processing a packed profile in unpack_profile() described like   \"profile :ns::samba-dcerpcd /usr/lib*/samba/{,samba/}samba-dcerpcd {...}\"  a string \":samba-dcerpcd\" is unpacked as a fully-qualified name and then passed to aa_splitn_fqname().  aa_splitn_fqname() treats \":samba-dcerpcd\" as only containing a namespace. Thus it returns NULL for tmpname, meanwhile tmpns is non-NULL. Later aa_alloc_profile() crashes as the new profile name is NULL now.  general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 6 PID: 1657 Comm: apparmor_parser Not tainted 6.7.0-rc2-dirty #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 RIP: 0010:strlen+0x1e/0xa0 Call Trace:  \u003cTASK\u003e  ? strlen+0x1e/0xa0  aa_policy_init+0x1bb/0x230  aa_alloc_profile+0xb1/0x480  unpack_profile+0x3bc/0x4960  aa_unpack+0x309/0x15e0  aa_replace_profiles+0x213/0x33c0  policy_update+0x261/0x370  profile_replace+0x20e/0x2a0  vfs_write+0x2af/0xe00  ksys_write+0x126/0x250  do_syscall_64+0x46/0xf0  entry_SYSCALL_64_after_hwframe+0x6e/0x76  \u003c/TASK\u003e ---[ end trace 0000000000000000 ]--- RIP: 0010:strlen+0x1e/0xa0  It seems such behaviour of aa_splitn_fqname() is expected and checked in other places where it is called (e.g. aa_remove_profiles). Well, there is an explicit comment \"a ns name without a following profile is allowed\" inside.  AFAICS, nothing can prevent unpacked \"name\" to be in form like \":samba-dcerpcd\" - it is passed from userspace.  Deny the whole profile set replacement in such case and inform user with EPROTO and an explaining message.  Found by Linux Verification Center (linuxtesting.org).","modified":"2026-09-15T09:02:47.599429560Z","published":"2024-02-22T17:15:08.377Z","upstream":["CVE-2023-52443"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2023-52443"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.76-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1~bpo11+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52443.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.15-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52443.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.15-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52443.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}