CVE-2021-47576
scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select()
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select() In resp_mode_select() sanity check the block descriptor len to avoid UAF. BUG: KASAN: use-after-free in resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 Read of size 1 at addr ffff888026670f50 by task scsicmd/15032 CPU: 1 PID: 15032 Comm: scsicmd Not tainted 5.15.0-01d0625 #15 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Call Trace: <TASK> dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:107 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:257 kasan_report.cold.14+0x7d/0x117 mm/kasan/report.c:443 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 schedule_resp+0x4af/0x1a10 drivers/scsi/scsi_debug.c:5483 scsi_debug_queuecommand+0x8c9/0x1e70 drivers/scsi/scsi_debug.c:7537 scsi_queue_rq+0x16b4/0x2d10 drivers/scsi/scsi_lib.c:1521 blk_mq_dispatch_rq_list+0xb9b/0x2700 block/blk-mq.c:1640 __blk_mq_sched_dispatch_requests+0x28f/0x590 block/blk-mq-sched.c:325 blk_mq_sched_dispatch_requests+0x105/0x190 block/blk-mq-sched.c:358 __blk_mq_run_hw_queue+0xe5/0x150 block/blk-mq.c:1762 __blk_mq_delay_run_hw_queue+0x4f8/0x5c0 block/blk-mq.c:1839 blk_mq_run_hw_queue+0x18d/0x350 block/blk-mq.c:1891 blk_mq_sched_insert_request+0x3db/0x4e0 block/blk-mq-sched.c:474 blk_execute_rq_nowait+0x16b/0x1c0 block/blk-exec.c:63 sg_common_write.isra.18+0xeb3/0x2000 drivers/scsi/sg.c:837 sg_new_write.isra.19+0x570/0x8c0 drivers/scsi/sg.c:775 sg_ioctl_common+0x14d6/0x2710 drivers/scsi/sg.c:941 sg_ioctl+0xa2/0x180 drivers/scsi/sg.c:1166 __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:52 do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:50 entry_SYSCALL_64_after_hwframe+0x44/0xae arch/x86/entry/entry_64.S:113
Timeline
ID reserved
By Linux
- 26 days later
· 26 days later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.26% · top 83% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Weakness
Affected products
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < adcecd50da6cab7b4957cba0606771dcc846c5a9
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < 90491283b4064220682e4b0687d07b05df01e3bf
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < 04181973c38f3d6a353f9246dcf7fee08024fd9e
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < b847ecff850719c46c95acd25a0d555dfd16e10d
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < a9078e791426c2cbbdf28a320c3670f6e0a611e6
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < dfc3fff63793c571147930b13c0f8c689c4281ac
- affected 231839102b54512ced7d3ee7fc9b8bcf5e3b583b – < e0a2c28da11e2c2b963fc01d50acbf03045ac732
- affected 2.6.19
- unaffected < 2.6.19
- unaffected 4.9.294 – ≤ 4.9.*
- unaffected 4.14.259 – ≤ 4.14.*
- unaffected 4.19.222 – ≤ 4.19.*
- unaffected 5.4.168 – ≤ 5.4.*
- unaffected 5.10.88 – ≤ 5.10.*
- unaffected 5.15.11 – ≤ 5.15.*
- unaffected 5.16 – ≤ *
References (7)
- https://git.kernel.org/stable/c/adcecd50da6cab7b4957cba0606771dcc846c5a9 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/90491283b4064220682e4b0687d07b05df01e3bf (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/04181973c38f3d6a353f9246dcf7fee08024fd9e (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/b847ecff850719c46c95acd25a0d555dfd16e10d (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a9078e791426c2cbbdf28a320c3670f6e0a611e6 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/dfc3fff63793c571147930b13c0f8c689c4281ac (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/e0a2c28da11e2c2b963fc01d50acbf03045ac732 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-47576)Record last updated .