CVE-2020-12657
published 2020-05-05CVE-2020-12657: An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.71%
50.0th percentile
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.6.7-1 (bookworm) | linux 5.6.7-1 (bookworm) |
| linux | linux_kernel | < 5.6.5 | 5.6.5 |
| linux | linux_kernel | >= 0 < 5.6.7-1 | 5.6.7-1 |
| linux | linux_kernel | >= 0 < 5.6.7-1 | 5.6.7-1 |
| linux | linux_kernel | >= 0 < 5.6.7-1 | 5.6.7-1 |
| linux | linux_kernel | >= 0 < 5.6.7-1 | 5.6.7-1 |
| linux | linux_kernel | >= 0 < 4.15.0-101.102 | 4.15.0-101.102 |
| linux | linux_kernel | >= 0 < 5.4.0-31.35 | 5.4.0-31.35 |
| linux | linux_kernel | >= 0 < 5.4.0-33.37 | 5.4.0-33.37 |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
| msrc | cm1_kernel_5.4.91-11_on_cbl_mariner_1.0 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu7.8HIGH
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
GHSA-9rm7-vxm7-wq42: An issue was discovered in the Linux kernel before 5
ghsa_unreviewed·2022-05-24
CVE-2020-12657 [MEDIUM] GHSA-9rm7-vxm7-wq42: An issue was discovered in the Linux kernel before 5
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
OSV
linux regression
osv·2020-05-28·CVSS 7.8
[HIGH] linux regression
linux regression
USN-4367-1 fixed vulnerabilities in the 5.4 Linux kernel. Unfortunately,
that update introduced a regression in overlayfs. This update corrects
the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565
OSV
linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gke-4.15, linux-hwe, linux-kvm, linux-oem, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities
osv·2020-05-28·CVSS 4.4
CVE-2020-11494 [MEDIUM] linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gke-4.15, linux-hwe, linux-kvm, linux-oem, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities
linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gke-4.15, linux-hwe, linux-kvm, linux-oem, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities
It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-11494)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)
David Gibson discovered that the Linux kernel on Power9 CPUs did not
properly save and restore Authority Mask registers state in some
situat
OSV
linux, linux-raspi2, linux-raspi2-5.3 regression
osv·2020-05-28·CVSS 7.8
[HIGH] linux, linux-raspi2, linux-raspi2-5.3 regression
linux, linux-raspi2, linux-raspi2-5.3 regression
USN-4369-1 fixed vulnerabilities in the 5.3 Linux kernel. Unfortunately,
that update introduced a regression in overlayfs. This update corrects
the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)
OSV
linux, linux-aws, linux-aws-5.3, linux-azure, linux-azure-5.3, linux-gcp, linux-gcp-5.3, linux-gke-5.3, linux-hwe, linux-kvm, linux-oracle, linux-oracle-5.3, linux-raspi2 vulnerabilities
osv·2020-05-24·CVSS 7.8
CVE-2019-19377 [HIGH] linux, linux-aws, linux-aws-5.3, linux-azure, linux-azure-5.3, linux-gcp, linux-gcp-5.3, linux-gke-5.3, linux-hwe, linux-kvm, linux-oracle, linux-oracle-5.3, linux-raspi2 vulnerabilities
linux, linux-aws, linux-aws-5.3, linux-azure, linux-azure-5.3, linux-gcp, linux-gcp-5.3, linux-gke-5.3, linux-hwe, linux-kvm, linux-oracle, linux-oracle-5.3, linux-raspi2 vulnerabilities
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)
It was discovered that the Serial CAN interface driver in the Linux kernel
did not p
OSV
linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oracle, linux-raspi, linux-riscv vulnerabilities
osv·2020-05-24·CVSS 7.8
CVE-2019-19377 [HIGH] linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oracle, linux-raspi, linux-riscv vulnerabilities
linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oracle, linux-raspi, linux-riscv vulnerabilities
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)
It was discovered that the block layer in the Linux kernel contained a race
condition leading to a use-after-free vulnerability.
OSV
linux-gke-5.0, linux-oem-osp1 vulnerabilities
osv·2020-05-19·CVSS 6.7
CVE-2019-19769 [MEDIUM] linux-gke-5.0, linux-oem-osp1 vulnerabilities
linux-gke-5.0, linux-oem-osp1 vulnerabilities
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)
It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-11494)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)
It was discovered that the OV51x USB Camera dev
OSV
CVE-2020-12657: An issue was discovered in the Linux kernel before 5
osv·2020-05-05·CVSS 7.8
CVE-2020-12657 [HIGH] CVE-2020-12657: An issue was discovered in the Linux kernel before 5
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
Ubuntu
Linux kernel regression
vendor_ubuntu·2020-05-28·CVSS 7.8
[HIGH] Linux kernel regression
Title: Linux kernel regression
Summary: USN-4369-1 introduced a regression in the Linux kernel.
USN-4369-1 fixed vulnerabilities in the 5.3 Linux kernel. Unfortunately,
that update introduced a regression in overlayfs. This update corrects
the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or
Ubuntu
Linux kernel regression
vendor_ubuntu·2020-05-28·CVSS 7.8
[HIGH] Linux kernel regression
Title: Linux kernel regression
Summary: USN-4367-1 introduced a regression in the Linux kernel.
USN-4367-1 fixed vulnerabilities in the 5.4 Linux kernel. Unfortunately,
that update introduced a regression in overlayfs. This update corrects
the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount opt
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2020-05-28·CVSS 4.4
CVE-2020-11494 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-11494)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)
David Gibson discovered that the Linux kernel on Power9 CPUs did not
properly save and restore Authority Mask registers state in some
situations. A local attacker in a guest VM could use this to cause a denial
of service (h
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2020-05-24·CVSS 7.8
CVE-2019-19377 [HIGH] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020-11565)
It was discovered that the block layer in the Linux kernel contained a race
condition leading to a use-after-free vulnerability. A loca
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2020-05-24·CVSS 7.8
CVE-2019-19377 [HIGH] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the btrfs implementation in the Linux kernel did not
properly detect that a block was marked dirty in some situations. An
attacker could use this to specially craft a file system image that, when
unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)
It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive informat
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2020-05-19·CVSS 6.7
CVE-2019-19769 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Tristan Madani discovered that the file locking implementation in the Linux
kernel contained a race condition. A local attacker could possibly use this
to cause a denial of service or expose sensitive information.
(CVE-2019-19769)
It was discovered that the Serial CAN interface driver in the Linux kernel
did not properly initialize data. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-11494)
It was discovered that the linux kernel did not properly validate certain
mount options to the tmpfs virtual memory file system. A local attacker
with the ability to specify mount options could use this to cause a denial
of service (system crash). (CVE-2020
Microsoft
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
vendor_msrc·2020-05-12·CVSS 7.8
CVE-2020-12657 [HIGH] CWE-416 An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
mitre: mitre
C
Red Hat
kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
vendor_redhat·2020-05-05·CVSS 7.8
CVE-2020-12657 [HIGH] CWE-416 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
A flaw was found in the Linux kernel's implementation of the BFQ IO scheduler. This flaw allows a local user able to groom system memory to cause kernel memory corruption and possible privilege escalation by abusing a race condition in the IO scheduler.
Mitigation: The default io scheduler for Red Hat Enterprise Linux 8 is the mq-deadline scheduler, however it can be
configured to any of the available schedulers available on the system on a per-device basis.
The schedulers in use can be verified by the block devices entry in sysfs, for example for "sda":
# cat /s
Debian
CVE-2020-12657: linux - An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-f...
vendor_debian·2020·CVSS 7.8
CVE-2020-12657 [HIGH] CVE-2020-12657: linux - An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-f...
An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.
Scope: local
bookworm: resolved (fixed in 5.6.7-1)
bullseye: resolved (fixed in 5.6.7-1)
forky: resolved (fixed in 5.6.7-1)
sid: resolved (fixed in 5.6.7-1)
trixie: resolved (fixed in 5.6.7-1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
bugzilla·2020-05-07·CVSS 7.8
CVE-2020-12657 [HIGH] CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body
An issue was discovered in the Linux kernels implementation of BFQ IO scheduler. A local user who is able to groom system memory may be able to cause kernel memory corruption and possibly privilege escalation through abusing a race condition in the IO scheduler.
Discussion:
Upstream Patch:
https://patchwork.kernel.org/patch/11447049/
Upstream Commit:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9
---
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1832867]
---
This was fixed for Fedora with the 5.5.18 stable kernel update.
---
Mitigation:
The default io scheduler for Red Hat Enterprise
Bugzilla
CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body [fedora-all]
bugzilla·2020-05-07·CVSS 7.8
CVE-2020-12657 [HIGH] CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body [fedora-all]
CVE-2020-12657 kernel: use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE: this issue af
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00022.htmlhttps://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.5https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9https://github.com/torvalds/linux/commit/2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9https://patchwork.kernel.org/patch/11447049/https://security.netapp.com/advisory/ntap-20200608-0001/https://usn.ubuntu.com/4363-1/https://usn.ubuntu.com/4367-1/https://usn.ubuntu.com/4368-1/https://usn.ubuntu.com/4369-1/http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00022.htmlhttps://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.5https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9https://github.com/torvalds/linux/commit/2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9https://patchwork.kernel.org/patch/11447049/https://security.netapp.com/advisory/ntap-20200608-0001/https://usn.ubuntu.com/4363-1/https://usn.ubuntu.com/4367-1/https://usn.ubuntu.com/4368-1/https://usn.ubuntu.com/4369-1/
2020-05-05
Published