Bluetooth: eir: Fix stack OOB write when prepending the Flags AD
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.1.178, 6.6.160, 6.12.97, 6.18.40, 7.1.5
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: eir: Fix stack OOB write when prepending the Flags AD eir_create_adv_data() builds the advertising data into a fixed-size buffer ("size", 31 for the legacy path). It may prepend a 3-byte "Flags" AD structure (LE_AD_NO_BREDR on an LE-only controller) and then copies the per-instance data without checking that it still fits: memcpy(ptr, adv->adv_data, adv->adv_data_len); tlv_data_max_len() only reserves those 3 bytes when the user-supplied flags carry a managed-flags bit, so an instance added with flags == 0 is accepted with adv_data_len up to the full buffer. At advertise time the flags are still prepended, and the memcpy() writes 3 + adv_data_len bytes into the size-byte buffer: BUG: KASAN: stack-out-of-bounds in eir_create_adv_data (net/bluetooth/eir.c:301) Write of size 31 at addr ffff88800a547bdc by task kworker/u9:0/65 Workqueue: hci0 hci_cmd_sync_work __asan_memcpy (mm/kasan/shadow.c:106) eir_create_adv_data (net/bluetooth/eir.c:301) hci_update_adv_data_sync (net/bluetooth/hci_sync.c:1310) hci_schedule_adv_instance_sync (net/bluetooth/hci_sync.c:1817) hci_cmd_sync_work (net/bluetooth/hci_sync.c:332) This frame has 1 object: [32, 64) 'cp' The "Flags" structure is added by the kernel, not requested by userspace, so only prepend it when it fits together with the instance advertising data; when there is no room for both, drop the flags rather than the user-provided data. Reachable by a local user with CAP_NET_ADMIN owning an LE-only controller on the legacy advertising path.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in 0f0b6232af56441d0a2dcb173cc4f8d8aab39014; From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in 9174992ee1045c9c96e53eecda64f49dd7e8fbba; From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in 09301f1fdf2aef8cce34d0c4650c30e7edb1ced9; From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in f1b4df9c260c51726da2e86e19322825fddeefd0; From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in 57077eeb586c42f124bc09e018449362223067b3; From b44133ff03be30b55f23036e62f403a3f7784fce · fixed in 6f5fb689fdf80bdd143f22a502f9eb1f3c85e286
- Linux Linux
4.1
- KernelLinux
From 4.1.0 · fixed in 6.1.178; From 6.2.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.97; From 6.13.0 · fixed in 6.18.40; From 6.19.0 · fixed in 7.1.5