tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf()
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.
Summary
In the Linux kernel, the following vulnerability has been resolved: tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf() A null pointer dereference can happen when attempting to access the "gsm->receive()" function in gsmld_receive_buf(). Currently, the code assumes that gsm->recieve is only called after MUX activation. Since the gsmld_receive_buf() function can be accessed without the need to initialize the MUX, the gsm->receive() function will not be set and a NULL pointer dereference will occur. Fix this by avoiding the call to "gsm->receive()" in case the function is not initialized by adding a sanity check. Call Trace: <TASK> gsmld_receive_buf+0x1c2/0x2f0 drivers/tty/n_gsm.c:2861 tiocsti drivers/tty/tty_io.c:2293 [inline] tty_ioctl+0xa75/0x15d0 drivers/tty/tty_io.c:2692 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.18.18 to before 5.19 | 5.19 | Patch available | CNA |
| Linux | Linux | 5.15.61 to before 5.15.66; 5.19.2 to before 5.19.8 | 5.15.66, 5.19.8 | Patch available | CNA |
- Linux VendorLinux Affected 5.18.18 to before 5.19 Fixed in 5.19 Patch available CNA
- Linux VendorLinux Affected 5.15.61 to before 5.15.66; 5.19.2 to before 5.19.8 Fixed in 5.15.66, 5.19.8 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.15.61 to before 5.15.66; 5.18.18 to before 5.19; 5.19.2 to before 5.19.8 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:* | 6.0 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:* | 6.0 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:* | 6.0 rc3 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.15.61 to before 5.15.66; 5.18.18 to before 5.19; 5.19.2 to before 5.19.8 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:* Versions 6.0 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:* Versions 6.0 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:* Versions 6.0 rc3 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.19
- Fix · CNA Linux (Linux) Fixed in 5.15.66, 5.19.8
Red Hat 3 advisories
- RHSA-2024:3138 Released 2024-05-22 · Red Hat rating Moderatekernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.el8_10, kernel-4.18.0-553.el8_10, kernel-abi-stablelists-4.18.0-553.el8_10 +19
- Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.el8_10
- RHSA-2024:2621 Released 2024-04-30 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder EUS (v.8.8) kernel-tools-libs-devel-4.18.0-477.55.1.el8_8
- Red Hat Enterprise Linux BaseOS EUS (v.8.8) bpftool-4.18.0-477.55.1.el8_8, kernel-4.18.0-477.55.1.el8_8, kernel-abi-stablelists-4.18.0-477.55.1.el8_8 +19
- RHSA-2024:2394 Released 2024-04-30 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-427.13.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.13.1.el9_4, kernel-64k-devel-5.14.0-427.13.1.el9_4 +11
- Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.3.0-427.13.1.el9_4, kernel-5.14.0-427.13.1.el9_4, kernel-64k-5.14.0-427.13.1.el9_4 +29
- Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-427.13.1.el9_4, libperf-5.14.0-427.13.1.el9_4
- Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-427.13.1.el9_4, kernel-rt-core-5.14.0-427.13.1.el9_4, kernel-rt-debug-5.14.0-427.13.1.el9_4 +11
- Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-427.13.1.el9_4, kernel-rt-core-5.14.0-427.13.1.el9_4, kernel-rt-debug-5.14.0-427.13.1.el9_4 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat CodeReady Linux Builder EUS (v.8.8) | Fixed | RHSA-2024:2621 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2024:3138 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux BaseOS EUS (v.8.8) | Fixed | RHSA-2024:2621 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2024:3138 |
| Red Hat Enterprise Linux CRB (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux NFV (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux RT (v. 9) | Fixed | RHSA-2024:2394 |
Not affected: 5 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2022-49940
- 2026-10-03 Alias added: GHSA-52j6-g7fj-mfjm
References
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- 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-2022-49940 · CVE Program
- CVE-2022-49940 · NVD
- FIRST EPSS
- GHSA-52j6-g7fj-mfjm · GitHub Advisory Database · CC BY 4.0
- CVE-2022-49940 · 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