CVE-2026-23461
published 2026-04-03CVE-2026-23461: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca…
PriorityP345high8.8CVSS 3.1
AVAACLPRNUINSUCHIHAH
EPSS
0.23%
13.4th percentile
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in
hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to
conn->users. However, l2cap_register_user() and l2cap_unregister_user()
don't use conn->lock, creating a race condition where these functions can
access conn->users and conn->hchan concurrently with l2cap_conn_del().
This can lead to use-after-free and list corruption bugs, as reported
by syzbot.
Fix this by changing l2cap_register_user() and l2cap_unregister_user()
to use conn->lock instead of hci_dev_lock(), ensuring consistent locking
for the l2cap_conn structure.
Affected
52 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.19.10-1 (forky) | linux 6.19.10-1 (forky) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 6.12.20 < 6.12.78 | 6.12.78 |
| linux | linux | >= 6.13.8 < 6.14 | 6.14 |
| linux | linux | >= 6.6.84 < 6.6.130 | 6.6.130 |
| linux | linux | >= ab4eedb790cae44313759b50fe47da285e2519d5 < da3000cbe4851458a22be38bb18c0689c39fdd5f | da3000cbe4851458a22be38bb18c0689c39fdd5f |
| linux | linux | >= ab4eedb790cae44313759b50fe47da285e2519d5 < 71030f3b3015a412133a805ff47970cdcf30c2b8 | 71030f3b3015a412133a805ff47970cdcf30c2b8 |
| linux | linux | >= ab4eedb790cae44313759b50fe47da285e2519d5 < 752a6c9596dd25efd6978a73ff21f3b592668f4a | 752a6c9596dd25efd6978a73ff21f3b592668f4a |
| linux | linux | >= efc30877bd4bc85fefe98d80af60fafc86e5775e < 11a87dd5df428a4b79a84d2790cac7f3c73f1f0d | 11a87dd5df428a4b79a84d2790cac7f3c73f1f0d |
| linux | linux | >= f87271d21dd4ee83857ca11b94e7b4952749bbae < c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf | c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.19.10-1 | 6.19.10-1 |
| linux | linux_kernel | >= 6.12.20 < 6.12.78 | 6.12.78 |
| linux | linux_kernel | >= 6.13.8 < 6.14 | 6.14 |
| linux | linux_kernel | >= 6.14.1 < 6.18.20 | 6.18.20 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat5.5MEDIUM
vendor_ubuntu2.0LOW
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Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-08-20·CVSS 2.0
CVE-2026-45855 [LOW] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values.
Ubuntu
Linux kernel (HWE) vulnerabilities
vendor_ubuntu·2026-07-28·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (HWE) vulnerabilities
Title: Linux kernel (HWE) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local a
Ubuntu
Linux kernel (Azure CVM) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (Azure CVM) vulnerabilities
Title: Linux kernel (Azure CVM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A l
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (Azure FIPS) vulnerabilities
Title: Linux kernel (Azure FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A
Ubuntu
Linux kernel (Azure CVM) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-43129 [LOW] Linux kernel (Azure CVM) vulnerabilities
Title: Linux kernel (Azure CVM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A l
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local
Ubuntu
Linux kernel (AWS) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (AWS) vulnerabilities
Title: Linux kernel (AWS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local a
Ubuntu
Linux kernel (Oracle) vulnerabilities
vendor_ubuntu·2026-07-23·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (Oracle) vulnerabilities
Title: Linux kernel (Oracle) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A loca
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-07-23·CVSS 2.0
CVE-2026-43129 [LOW] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A loca
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-23·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local attacke
Ubuntu
Linux kernel (GCP FIPS) vulnerabilities
vendor_ubuntu·2026-07-21·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel (GCP FIPS) vulnerabilities
Title: Linux kernel (GCP FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A lo
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-20·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local attacke
Red Hat
kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
vendor_redhat·2026-04-03·CVSS 5.5
CVE-2026-23461 [MEDIUM] CWE-413 kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in
hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to
conn->users. However, l2cap_register_user() and l2cap_unregister_user()
don't use conn->lock, creating a race condition where these functions can
access conn->users and conn->hchan concurrently with l2cap_conn_del().
This can lead to use-after-free and list corruption bugs, as reported
by syzbot.
Fix this by changing l2cap_register_user() and l2cap_unregister_user()
to use conn->lock instead of hci_dev_lock(), ensuring consistent locking
for the l2cap_conn
Debian
CVE-2026-23461: linux - In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ...
vendor_debian·2026
CVE-2026-23461 [LOW] CVE-2026-23461: linux - In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ...
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to conn->users. However, l2cap_register_user() and l2cap_unregister_user() don't use conn->lock, creating a race condition where these functions can access conn->users and conn->hchan concurrently with l2cap_conn_del(). This can lead to use-after-free and list corruption bugs, as reported by syzbot. Fix this by changing l2cap_register_user() and l2cap_unregister_user() to use conn->lock instead of hci_dev_lock(), ensuring consistent locking for the l2cap_conn structure.
Scope: local
bookworm: resolved
bullseye: resolved
forky: re
OSV
CVE-2026-23461: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb
osv·2026-04-03
CVE-2026-23461 CVE-2026-23461: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to conn->users. However, l2cap_register_user() and l2cap_unregister_user() don't use conn->lock, creating a race condition where these functions can access conn->users and conn->hchan concurrently with l2cap_conn_del(). This can lead to use-after-free and list corruption bugs, as reported by syzbot. Fix this by changing l2cap_register_user() and l2cap_unregister_user() to use conn->lock instead of hci_dev_lock(), ensuring consistent locking for the l2cap_conn structure.
GHSA
GHSA-ggw5-jw3c-r95v: In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4ee
ghsa_unreviewed·2026-04-03
CVE-2026-23461 GHSA-ggw5-jw3c-r95v: In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4ee
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in
hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to
conn->users. However, l2cap_register_user() and l2cap_unregister_user()
don't use conn->lock, creating a race condition where these functions can
access conn->users and conn->hchan concurrently with l2cap_conn_del().
This can lead to use-after-free and list corruption bugs, as reported
by syzbot.
Fix this by changing l2cap_register_user() and l2cap_unregister_user()
to use conn->lock instead of hci_dev_lock(), ensuring consistent locking
for the l2cap_conn structure.
No detection rules found.
No public exploits indexed.
Wiz
CVE-2026-23461 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2026-23461 CVE-2026-23461 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-23461 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in
hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to
conn->users. However, l2cap_register_user() and l2cap_unregister_user()
don't use conn->lock, creating a race condition where these functions can
access conn->users and conn->hchan concurrently with l2cap_conn_del().
This can lead to use-after-free and list corruption bugs, as reported
by syzbot.
Fix this by changing l2cap_register_user() and l2cap_unregister_user()
to use conn->lock instead of hci_dev_lock(), ensuring consistent locking
for the l2cap
Bugzilla
CVE-2026-23461 kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
bugzilla·2026-04-03·CVSS 8.8
CVE-2026-23461 [HIGH] CVE-2026-23461 kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
CVE-2026-23461 kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in
hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to
conn->users. However, l2cap_register_user() and l2cap_unregister_user()
don't use conn->lock, creating a race condition where these functions can
access conn->users and conn->hchan concurrently with l2cap_conn_del().
This can lead to use-after-free and list corruption bugs, as reported
by syzbot.
Fix this by changing l2cap_register_user() and l2cap_unregister_user()
to use conn->lock instead of hci_dev_lock(), ensuring consistent locking
https://git.kernel.org/stable/c/11a87dd5df428a4b79a84d2790cac7f3c73f1f0dhttps://git.kernel.org/stable/c/71030f3b3015a412133a805ff47970cdcf30c2b8https://git.kernel.org/stable/c/752a6c9596dd25efd6978a73ff21f3b592668f4ahttps://git.kernel.org/stable/c/c22a5e659959eb77c2fbb58a5adfaf3c3dab7abfhttps://git.kernel.org/stable/c/da3000cbe4851458a22be38bb18c0689c39fdd5f
2026-04-03
Published