# CVE-2021-47029: mt76: connac: fix kernel warning adding monitor interface > A kernel warning in the mt76 driver when adding a monitor interface can lead to a denial of service condition. - **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:** No - **Published:** 28 Feb 2024 - **Updated:** 11 May 2026 - **Also known as:** GHSA-77r5-rg8x-qv78, UBUNTU-CVE-2021-47029 ## What is CVE-2021-47029? CVE-2021-47029 is a medium-severity denial of service vulnerability in Linux kernel, published on 28 Feb 2024. 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: mt76: connac: fix kernel warning adding monitor interface Fix the following kernel warning adding a monitor interface in mt76_connac_mcu_uni_add_dev routine. [ 507.984882] ------------[ cut here ]------------ [ 507.989515] WARNING: CPU: 1 PID: 3017 at mt76_connac_mcu_uni_add_dev+0x178/0x190 [mt76_connac_lib] [ 508.059379] CPU: 1 PID: 3017 Comm: ifconfig Not tainted 5.4.98 #0 [ 508.065461] Hardware name: MT7622_MT7531 RFB (DT) [ 508.070156] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 508.074939] pc : mt76_connac_mcu_uni_add_dev+0x178/0x190 [mt76_connac_lib] [ 508.081806] lr : mt7921_eeprom_init+0x1288/0x1cb8 [mt7921e] [ 508.087367] sp : ffffffc013a33930 [ 508.090671] x29: ffffffc013a33930 x28: ffffff801e628ac0 [ 508.095973] x27: ffffff801c7f1200 x26: ffffff801c7eb008 [ 508.101275] x25: ffffff801c7eaef0 x24: ffffff801d025610 [ 508.106577] x23: ffffff801d022990 x22: ffffff801d024de8 [ 508.111879] x21: ffffff801d0226a0 x20: ffffff801c7eaee8 [ 508.117181] x19: ffffff801d0226a0 x18: 000000005d00b000 [ 508.122482] x17: 00000000ffffffff x16: 0000000000000000 [ 508.127785] x15: 0000000000000080 x14: ffffff801d704000 [ 508.133087] x13: 0000000000000040 x12: 0000000000000002 [ 508.138389] x11: 000000000000000c x10: 0000000000000000 [ 508.143691] x9 : 0000000000000020 x8 : 0000000000000001 [ 508.148992] x7 : 0000000000000000 x6 : 0000000000000000 [ 508.154294] x5 : ffffff801c7eaee8 x4 : 0000000000000006 [ 508.159596] x3 : 0000000000000001 x2 : 0000000000000000 [ 508.164898] x1 : ffffff801c7eac08 x0 : ffffff801d0226a0 [ 508.170200] Call trace: [ 508.172640] mt76_connac_mcu_uni_add_dev+0x178/0x190 [mt76_connac_lib] [ 508.179159] mt7921_eeprom_init+0x1288/0x1cb8 [mt7921e] [ 508.184394] drv_add_interface+0x34/0x88 [mac80211] [ 508.189271] ieee80211_add_virtual_monitor+0xe0/0xb48 [mac80211] [ 508.195277] ieee80211_do_open+0x86c/0x918 [mac80211] [ 508.200328] ieee80211_do_open+0x900/0x918 [mac80211] [ 508.205372] __dev_open+0xcc/0x150 [ 508.208763] __dev_change_flags+0x134/0x198 [ 508.212937] dev_change_flags+0x20/0x60 [ 508.216764] devinet_ioctl+0x3e8/0x748 [ 508.220503] inet_ioctl+0x1e4/0x350 [ 508.223983] sock_do_ioctl+0x48/0x2a0 [ 508.227635] sock_ioctl+0x310/0x4f8 [ 508.231116] do_vfs_ioctl+0xa4/0xac0 [ 508.234681] ksys_ioctl+0x44/0x90 [ 508.237985] __arm64_sys_ioctl+0x1c/0x48 [ 508.241901] el0_svc_common.constprop.1+0x7c/0x100 [ 508.246681] el0_svc_handler+0x18/0x20 [ 508.250421] el0_svc+0x8/0x1c8 [ 508.253465] ---[ end trace c7b90fee13d72c39 ]--- [ 508.261278] ------------[ cut here ]------------ ## Which versions are affected by CVE-2021-47029? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2021-47029? No fix has been published for CVE-2021-47029 yet. Limit exposure of the affected software until one is available. ## Is CVE-2021-47029 being exploited? There is no known exploitation of CVE-2021-47029 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2021-47029 and fix it if it is affected. What it is: CVE-2021-47029 is a medium-severity denial of service vulnerability in Linux kernel, published on 28 Feb 2024. 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-2021-47029 in the wild and no public exploit code. Affected product: Linux kernel. 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-2021-47029/ (Markdown: https://insights.sbomify.com/CVE-2021-47029/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47029 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47029 - OSV: https://osv.dev/vulnerability/CVE-2021-47029 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-47029/ Summaries are generated and may contain mistakes; the official description above is the record.