Local privilege escalation via rawdata dedup race
Published Jul 19, 2026 · Updated Jul 19, 2026
Use-after-free in the Linux kernel AppArmor subsystem allows local users to escalate privileges through concurrent policy operations. The aa_replace_profiles() rawdata deduplication loop unconditionally increments a zero pcount for a dying aa_loaddata entry that remains linked before deferred removal. Reaching the race requires CAP_MAC_ADMIN and policy-view rights; the corrupted refcount enables kernel-memory disclosure or writes, privilege escalation, and a host crash.
Summary
What happened
Use-after-free in the Linux kernel AppArmor subsystem allows local users to escalate privileges through concurrent policy operations. The aa_replace_profiles() rawdata deduplication loop unconditionally increments a zero pcount for a dying aa_loaddata entry that remains linked before deferred removal. Reaching the race requires CAP_MAC_ADMIN and policy-view rights; the corrupted refcount enables kernel-memory disclosure or writes, privilege escalation, and a host crash.
The record
- CVE
- CVE-2026-63827
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3b8e77c7abab40e6de9ad9de730d77984a498840
- Affected versionversion=5.10.253 <5.11
- Affected versionversion=5.15.203 <5.16
- Affected versionversion=6.1.169 <6.1.177
- Affected versionversion=6.12.77 <6.12.95
- Affected versionversion=6.18.18 <6.18.38
- Affected versionversion=6.19.8 <6.20
- Affected versionversion=6.6.130 <6.6.144
- Affected versionversion=6b6ba87579c7e7c669e0bec91823e7fb693bc5df <a7a2890028f16e5b0af0bb005d80fcb32559cca3
- Affected versionversion=6ef1f2926c41ab96952d9696d55a052f1b3a9418 <15fd83a1e42ede15070968806bb6c8b1a5170688
- Affected versionversion=7.0
- Affected versionversion=763e838adc3c7ec5a7df2990ce84cad951e42721
- Affected versionversion=a0b7091c4de45a7325c8780e6934a894f92ac86b <5e34fa9f6f7cd688ae153fff13139a5cf2d42339
- Affected versionversion=a0b7091c4de45a7325c8780e6934a894f92ac86b <6f060496d03e4dc560a40f73770bd08335cb7a27
- Affected versionversion=af782cc8871e3683ddd5a3cd2f7df526599863a9 <c3ca2631073b2cef06824fd2bfc452ff7a1023de
- Affected versionversion=d9d8560b9b7932f8cffc4c068c14289220900f79
- Affected versionversion=f9761add6d100962a23996cb68f3d6abdd4d1815 <ce261a20b41db522e320a41bbf1292bf85af66df
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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