# CVE-2025-37781: i2c: cros-ec-tunnel: defer probe if parent EC is not present > A NULL pointer dereference in the Linux kernel's cros-ec-tunnel driver causes a system crash when the parent EC device is missing. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 1 May 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2025-37781, DEBIAN-CVE-2025-37781, GHSA-mrq3-qx26-xjxj, ROOT-OS-DEBIAN-12-CVE-2025-37781, ROOT-OS-UBUNTU-2204-CVE-2025-37781, ROOT-OS-UBUNTU-2404-CVE-2025-37781, UBUNTU-CVE-2025-37781 ## What is CVE-2025-37781? CVE-2025-37781 is a medium-severity vulnerability in Debian Debian Linux, published on 1 May 2025. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description In the Linux kernel, the following vulnerability has been resolved: i2c: cros-ec-tunnel: defer probe if parent EC is not present When i2c-cros-ec-tunnel and the EC driver are built-in, the EC parent device will not be found, leading to NULL pointer dereference. That can also be reproduced by unbinding the controller driver and then loading i2c-cros-ec-tunnel module (or binding the device). [ 271.991245] BUG: kernel NULL pointer dereference, address: 0000000000000058 [ 271.998215] #PF: supervisor read access in kernel mode [ 272.003351] #PF: error_code(0x0000) - not-present page [ 272.008485] PGD 0 P4D 0 [ 272.011022] Oops: Oops: 0000 [#1] SMP NOPTI [ 272.015207] CPU: 0 UID: 0 PID: 3859 Comm: insmod Tainted: G S 6.15.0-rc1-00004-g44722359ed83 #30 PREEMPT(full) 3c7fb39a552e7d949de2ad921a7d6588d3a4fdc5 [ 272.030312] Tainted: [S]=CPU_OUT_OF_SPEC [ 272.034233] Hardware name: HP Berknip/Berknip, BIOS Google_Berknip.13434.356.0 05/17/2021 [ 272.042400] RIP: 0010:ec_i2c_probe+0x2b/0x1c0 [i2c_cros_ec_tunnel] [ 272.048577] Code: 1f 44 00 00 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 05 06 a0 6c e7 48 89 44 24 08 4c 8d 7f 10 48 8b 47 50 4c 8b 60 78 <49> 83 7c 24 58 00 0f 84 2f 01 00 00 48 89 fb be 30 06 00 00 4c 9 [ 272.067317] RSP: 0018:ffffa32082a03940 EFLAGS: 00010282 [ 272.072541] RAX: ffff969580b6a810 RBX: ffff969580b68c10 RCX: 0000000000000000 [ 272.079672] RDX: 0000000000000000 RSI: 0000000000000282 RDI: ffff969580b68c00 [ 272.086804] RBP: 00000000fffffdfb R08: 0000000000000000 R09: 0000000000000000 [ 272.093936] R10: 0000000000000000 R11: ffffffffc0600000 R12: 0000000000000000 [ 272.101067] R13: ffffffffa666fbb8 R14: ffffffffc05b5528 R15: ffff969580b68c10 [ 272.108198] FS: 00007b930906fc40(0000) GS:ffff969603149000(0000) knlGS:0000000000000000 [ 272.116282] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 272.122024] CR2: 0000000000000058 CR3: 000000012631c000 CR4: 00000000003506f0 [ 272.129155] Call Trace: [ 272.131606] [ 272.133709] ? acpi_dev_pm_attach+0xdd/0x110 [ 272.137985] platform_probe+0x69/0xa0 [ 272.141652] really_probe+0x152/0x310 [ 272.145318] __driver_probe_device+0x77/0x110 [ 272.149678] driver_probe_device+0x1e/0x190 [ 272.153864] __driver_attach+0x10b/0x1e0 [ 272.157790] ? driver_attach+0x20/0x20 [ 272.161542] bus_for_each_dev+0x107/0x150 [ 272.165553] bus_add_driver+0x15d/0x270 [ 272.169392] driver_register+0x65/0x110 [ 272.173232] ? cleanup_module+0xa80/0xa80 [i2c_cros_ec_tunnel 3a00532f3f4af4a9eade753f86b0f8dd4e4e5698] [ 272.182617] do_one_initcall+0x110/0x350 [ 272.186543] ? security_kernfs_init_security+0x49/0xd0 [ 272.191682] ? __kernfs_new_node+0x1b9/0x240 [ 272.195954] ? security_kernfs_init_security+0x49/0xd0 [ 272.201093] ? __kernfs_new_node+0x1b9/0x240 [ 272.205365] ? kernfs_link_sibling+0x105/0x130 [ 272.209810] ? kernfs_next_descendant_post+0x1c/0xa0 [ 272.214773] ? kernfs_activate+0x57/0x70 [ 272.218699] ? kernfs_add_one+0x118/0x160 [ 272.222710] ? __kernfs_create_file+0x71/0xa0 [ 272.227069] ? sysfs_add_bin_file_mode_ns+0xd6/0x110 [ 272.232033] ? internal_create_group+0x453/0x4a0 [ 272.236651] ? __vunmap_range_noflush+0x214/0x2d0 [ 272.241355] ? __free_frozen_pages+0x1dc/0x420 [ 272.245799] ? free_vmap_area_noflush+0x10a/0x1c0 [ 272.250505] ? load_module+0x1509/0x16f0 [ 272.254431] do_init_module+0x60/0x230 [ 272.258181] __se_sys_finit_module+0x27a/0x370 [ 272.262627] do_syscall_64+0x6a/0xf0 [ 272.266206] ? do_syscall_64+0x76/0xf0 [ 272.269956] ? irqentry_exit_to_user_mode+0x79/0x90 [ 272.274836] entry_SYSCALL_64_after_hwframe+0x55/0x5d [ 272.279887] RIP: 0033:0x7b9309168d39 [ 272.283466] Code: 5b 41 5c 5d c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d af 40 0c 00 f7 d8 64 89 01 8 [ 272.302210] RSP: 002b:00007fff50f1a288 EFLAGS: 00000246 ORIG_RAX: 000 ---truncated--- Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2025-37781? It affects 2 products. Products: Debian Debian Linux, Linux kernel. ## How do I fix CVE-2025-37781? Apply the vendor's patch. ## Is CVE-2025-37781 being exploited? There is no known exploitation of CVE-2025-37781 in the wild and no public exploit code. ## Other vulnerabilities in Debian Debian Linux - [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild) - [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild) - [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild) - [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild) - [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2025-37781 and fix it if it is affected. What it is: CVE-2025-37781 is a medium-severity vulnerability in Debian Debian Linux, published on 1 May 2025. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2025-37781 in the wild and no public exploit code. Affected product: Debian Debian Linux. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2025-37781/ (Markdown: https://insights.sbomify.com/CVE-2025-37781/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2025-37781 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-37781 - OSV: https://osv.dev/vulnerability/CVE-2025-37781 --- From sbomify Insights: https://insights.sbomify.com/CVE-2025-37781/ Summaries are generated and may contain mistakes; the official description above is the record.