# CVE-2025-38020: net/mlx5e: Disable MACsec offload for uplink representor profile > A null pointer dereference in the Linux kernel mlx5e driver causes a system crash when MACsec offload is enabled on uplink representors. - **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:** 18 Jun 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2025-38020, DEBIAN-CVE-2025-38020, GHSA-gvv6-qc64-74pq, ROOT-OS-DEBIAN-12-CVE-2025-38020, ROOT-OS-UBUNTU-2204-CVE-2025-38020, ROOT-OS-UBUNTU-2404-CVE-2025-38020, UBUNTU-CVE-2025-38020 ## What is CVE-2025-38020? CVE-2025-38020 is a medium-severity vulnerability in Debian Debian Linux, published on 18 Jun 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: net/mlx5e: Disable MACsec offload for uplink representor profile MACsec offload is not supported in switchdev mode for uplink representors. When switching to the uplink representor profile, the MACsec offload feature must be cleared from the netdevice's features. If left enabled, attempts to add offloads result in a null pointer dereference, as the uplink representor does not support MACsec offload even though the feature bit remains set. Clear NETIF_F_HW_MACSEC in mlx5e_fix_uplink_rep_features(). Kernel log: Oops: general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f] CPU: 29 UID: 0 PID: 4714 Comm: ip Not tainted 6.14.0-rc4_for_upstream_debug_2025_03_02_17_35 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:__mutex_lock+0x128/0x1dd0 Code: d0 7c 08 84 d2 0f 85 ad 15 00 00 8b 35 91 5c fe 03 85 f6 75 29 49 8d 7e 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a6 15 00 00 4d 3b 76 60 0f 85 fd 0b 00 00 65 ff RSP: 0018:ffff888147a4f160 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 000000000000000f RSI: 0000000000000000 RDI: 0000000000000078 RBP: ffff888147a4f2e0 R08: ffffffffa05d2c19 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000018 R15: ffff888152de0000 FS: 00007f855e27d800(0000) GS:ffff88881ee80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004e5768 CR3: 000000013ae7c005 CR4: 0000000000372eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 Call Trace: ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core] ? __mutex_lock+0x128/0x1dd0 ? lockdep_set_lock_cmp_fn+0x190/0x190 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core] ? mutex_lock_io_nested+0x1ae0/0x1ae0 ? lock_acquire+0x1c2/0x530 ? macsec_upd_offload+0x145/0x380 ? lockdep_hardirqs_on_prepare+0x400/0x400 ? kasan_save_stack+0x30/0x40 ? kasan_save_stack+0x20/0x40 ? kasan_save_track+0x10/0x30 ? __kasan_kmalloc+0x77/0x90 ? __kmalloc_noprof+0x249/0x6b0 ? genl_family_rcv_msg_attrs_parse.constprop.0+0xb5/0x240 ? mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core] mlx5e_macsec_add_secy+0xf9/0x700 [mlx5_core] ? mlx5e_macsec_add_rxsa+0x11a0/0x11a0 [mlx5_core] macsec_update_offload+0x26c/0x820 ? macsec_set_mac_address+0x4b0/0x4b0 ? lockdep_hardirqs_on_prepare+0x284/0x400 ? _raw_spin_unlock_irqrestore+0x47/0x50 macsec_upd_offload+0x2c8/0x380 ? macsec_update_offload+0x820/0x820 ? __nla_parse+0x22/0x30 ? genl_family_rcv_msg_attrs_parse.constprop.0+0x15e/0x240 genl_family_rcv_msg_doit+0x1cc/0x2a0 ? genl_family_rcv_msg_attrs_parse.constprop.0+0x240/0x240 ? cap_capable+0xd4/0x330 genl_rcv_msg+0x3ea/0x670 ? genl_family_rcv_msg_dumpit+0x2a0/0x2a0 ? lockdep_set_lock_cmp_fn+0x190/0x190 ? macsec_update_offload+0x820/0x820 netlink_rcv_skb+0x12b/0x390 ? genl_family_rcv_msg_dumpit+0x2a0/0x2a0 ? netlink_ack+0xd80/0xd80 ? rwsem_down_read_slowpath+0xf90/0xf90 ? netlink_deliver_tap+0xcd/0xac0 ? netlink_deliver_tap+0x155/0xac0 ? _copy_from_iter+0x1bb/0x12c0 genl_rcv+0x24/0x40 netlink_unicast+0x440/0x700 ? netlink_attachskb+0x760/0x760 ? lock_acquire+0x1c2/0x530 ? __might_fault+0xbb/0x170 netlink_sendmsg+0x749/0xc10 ? netlink_unicast+0x700/0x700 ? __might_fault+0xbb/0x170 ? netlink_unicast+0x700/0x700 __sock_sendmsg+0xc5/0x190 ____sys_sendmsg+0x53f/0x760 ? import_iovec+0x7/0x10 ? kernel_sendmsg+0x30/0x30 ? __copy_msghdr+0x3c0/0x3c0 ? filter_irq_stacks+0x90/0x90 ? stack_depot_save_flags+0x28/0xa30 ___sys_sen ---truncated--- Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2025-38020? It affects 2 products. Products: Debian Debian Linux, Linux kernel. ## How do I fix CVE-2025-38020? Apply the vendor's patch. ## Is CVE-2025-38020 being exploited? There is no known exploitation of CVE-2025-38020 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-2025-38020 and fix it if it is affected. What it is: CVE-2025-38020 is a medium-severity vulnerability in Debian Debian Linux, published on 18 Jun 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-2025-38020 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-2025-38020/ (Markdown: https://insights.sbomify.com/CVE-2025-38020/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38020 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38020 - OSV: https://osv.dev/vulnerability/CVE-2025-38020 --- From sbomify Insights: https://insights.sbomify.com/CVE-2025-38020/ Summaries are generated and may contain mistakes; the official description above is the record.