mISDN: annotate data-race around dev->work
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: mISDN: annotate data-race around dev->work dev->work can re read locklessly in mISDN_read() and mISDN_poll(). Add READ_ONCE()/WRITE_ONCE() annotations. BUG: KCSAN: data-race in mISDN_ioctl / mISDN_read write to 0xffff88812d848280 of 4 bytes by task 10864 on cpu 1: misdn_add_timer drivers/isdn/mISDN/timerdev.c:175 [inline] mISDN_ioctl+0x2fb/0x550 drivers/isdn/mISDN/timerdev.c:233 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583 x64_sys_call+0x14b0/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd8/0x2c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff88812d848280 of 4 bytes by task 10857 on cpu 0: mISDN_read+0x1f2/0x470 drivers/isdn/mISDN/timerdev.c:112 do_loop_readv_writev fs/read_write.c:847 [inline] vfs_readv+0x3fb/0x690 fs/read_write.c:1020 do_readv+0xe7/0x210 fs/read_write.c:1080 __do_sys_readv fs/read_write.c:1165 [inline] __se_sys_readv fs/read_write.c:1162 [inline] __x64_sys_readv+0x45/0x50 fs/read_write.c:1162 x64_sys_call+0x2831/0x3000 arch/x86/include/generated/asm/syscalls_64.h:20 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd8/0x2c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000 -> 0x00000001
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.27 and later | 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8, 6.19 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.27 and later Fixed in 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8, 6.19 Patch available CNA
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.27 to before 5.10.249; 5.11 to before 5.15.199; 5.16 to before 6.1.162; 6.2 to before 6.6.122; 6.7 to before 6.12.68; 6.13 to before 6.18.8 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* | 6.19 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* | 6.19 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* | 6.19 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* | 6.19 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* | 6.19 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* | 6.19 rc6 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.27 to before 5.10.249; 5.11 to before 5.15.199; 5.16 to before 6.1.162; 6.2 to before 6.6.122; 6.7 to before 6.12.68; 6.13 to before 6.18.8 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* Versions 6.19 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* Versions 6.19 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* Versions 6.19 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* Versions 6.19 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* Versions 6.19 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* Versions 6.19 rc6 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8, 6.19
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
Not affected: 2 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2026-23121
- 2026-10-03 Alias added: GHSA-h3v4-524h-5jpx
- 2026-10-19 Weakness changed · CISA ADP
References
Patch 7
- https://git.kernel.org/stable/c/d5d99cb9e0839093cd53aa3b28176fce2f820ca0
- https://git.kernel.org/stable/c/13f3b3b87068898056db4c79ee67052fbde11d43
- https://git.kernel.org/stable/c/accc3f8266d2a49881dbcf78c459477f4efa0ff3
- https://git.kernel.org/stable/c/fc8ba17fd3337bd8b1913c30b95df0fee00d8fb7
- https://git.kernel.org/stable/c/aa6e33cd74ca4965f2bbcb025e0b672fb0168a69
- https://git.kernel.org/stable/c/7ac345a93af31358e18e9606eb7b354691bf6757
- https://git.kernel.org/stable/c/8175dbf174d487afab81e936a862a8d9b8a1ccb6
More Linux Kernel vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2026-23121 · CVE Program
- CVE-2026-23121 · NVD
- FIRST EPSS
- GHSA-h3v4-524h-5jpx · GitHub Advisory Database · CC BY 4.0
- CVE-2026-23121 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences