CVE-2021-47646
published 2025-02-26CVE-2021-47646: In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happened to be…
PriorityP337high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.28%
20.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
Revert "Revert "block, bfq: honor already-setup queue merges""
A crash [1] happened to be triggered in conjunction with commit
2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The
latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq:
honor already-setup queue merges""). Yet, the reverted commit was not
the one introducing the bug. In fact, it actually triggered a UAF
introduced by a different commit, and now fixed by commit d29bd41428cf
("block, bfq: reset last_bfqq_created on group change").
So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq:
honor already-setup queue merges") out. This commit restores it.
[1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.17.3-1 (bookworm) | linux 5.17.3-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 430a67f9d6169a7b3e328bceb2ef9542e4153c7c < 65d8a737452e88f251fe5d925371de6d606df613 | 65d8a737452e88f251fe5d925371de6d606df613 |
| linux | linux | >= 430a67f9d6169a7b3e328bceb2ef9542e4153c7c < abc2129e646af7b43025d90a071f83043f1ae76c | abc2129e646af7b43025d90a071f83043f1ae76c |
| linux | linux | >= 430a67f9d6169a7b3e328bceb2ef9542e4153c7c < 4083925bd6dc89216d156474a8076feec904e607 | 4083925bd6dc89216d156474a8076feec904e607 |
| linux | linux | >= 430a67f9d6169a7b3e328bceb2ef9542e4153c7c < 15729ff8143f8135b03988a100a19e66d7cb7ecd | 15729ff8143f8135b03988a100a19e66d7cb7ecd |
| linux | linux_kernel | < 4.19.238 | 4.19.238 |
| linux | linux_kernel | >= 0 < 5.10.113-1 | 5.10.113-1 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| linux | linux_kernel | >= 4.20 < 5.4.189 | 5.4.189 |
| linux | linux_kernel | >= 5.11 < 5.15.33 | 5.15.33 |
| linux | linux_kernel | >= 5.16 < 5.16.19 | 5.16.19 |
| linux | linux_kernel | >= 5.17 < 5.17.2 | 5.17.2 |
| linux | linux_kernel | >= 5.5 < 5.10.110 | 5.10.110 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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VulDB
Linux Kernel up to 5.17.1 last_bfqq_created denial of service
vuldb·2026-08-15·CVSS 7.8
CVE-2021-47646 [HIGH] Linux Kernel up to 5.17.1 last_bfqq_created denial of service
A vulnerability classified as critical has been found in Linux Kernel up to 5.17.1. Affected by this issue is the function last_bfqq_created. This manipulation causes denial of service.
This vulnerability is handled as CVE-2021-47646. The attack can only be done within the local network. There is not any exploit available.
It is recommended to upgrade the affected component.
GHSA
GHSA-8qgg-vj9j-hh4r: In the Linux kernel, the following vulnerability has been resolved:
Revert "Revert "block, bfq: honor already-setup queue merges""
A crash [1] happe
ghsa_unreviewed·2025-02-27
CVE-2021-47646 [HIGH] CWE-416 GHSA-8qgg-vj9j-hh4r: In the Linux kernel, the following vulnerability has been resolved:
Revert "Revert "block, bfq: honor already-setup queue merges""
A crash [1] happe
In the Linux kernel, the following vulnerability has been resolved:
Revert "Revert "block, bfq: honor already-setup queue merges""
A crash [1] happened to be triggered in conjunction with commit
2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The
latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq:
honor already-setup queue merges""). Yet, the reverted commit was not
the one introducing the bug. In fact, it actually triggered a UAF
introduced by a different commit, and now fixed by commit d29bd41428cf
("block, bfq: reset last_bfqq_created on group change").
So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq:
honor already-setup queue merges") out. This commit restores it.
[1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
OSV
CVE-2021-47646: In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happene
osv·2025-02-26·CVSS 7.8
CVE-2021-47646 [HIGH] CVE-2021-47646: In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happene
In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happened to be triggered in conjunction with commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq: honor already-setup queue merges""). Yet, the reverted commit was not the one introducing the bug. In fact, it actually triggered a UAF introduced by a different commit, and now fixed by commit d29bd41428cf ("block, bfq: reset last_bfqq_created on group change"). So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges") out. This commit restores it. [1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Red Hat
kernel: Revert "Revert "block, bfq: honor already-setup queue merges""
vendor_redhat·2025-02-26·CVSS 7.8
CVE-2021-47646 [HIGH] CWE-416 kernel: Revert "Revert "block, bfq: honor already-setup queue merges""
kernel: Revert "Revert "block, bfq: honor already-setup queue merges""
In the Linux kernel, the following vulnerability has been resolved:
Revert "Revert "block, bfq: honor already-setup queue merges""
A crash [1] happened to be triggered in conjunction with commit
2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The
latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq:
honor already-setup queue merges""). Yet, the reverted commit was not
the one introducing the bug. In fact, it actually triggered a UAF
introduced by a different commit, and now fixed by commit d29bd41428cf
("block, bfq: reset last_bfqq_created on group change").
So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq:
honor already-setup queue merges") out. This commit restores it.
Debian
CVE-2021-47646: linux - In the Linux kernel, the following vulnerability has been resolved: Revert "Rev...
vendor_debian·2021·CVSS 7.8
CVE-2021-47646 [HIGH] CVE-2021-47646: linux - In the Linux kernel, the following vulnerability has been resolved: Revert "Rev...
In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happened to be triggered in conjunction with commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq: honor already-setup queue merges""). Yet, the reverted commit was not the one introducing the bug. In fact, it actually triggered a UAF introduced by a different commit, and now fixed by commit d29bd41428cf ("block, bfq: reset last_bfqq_created on group change"). So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges") out. This commit restores it. [1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Scope: local
book
No detection rules found.
No public exploits indexed.
2025-02-26
Published