# CVE-2021-47065: rtw88: Fix array overrun in rtw_get_tx_power_params() > An array overrun in the rtw88 wireless driver allows attackers to cause memory corruption, potentially leading to system crashes or code execution. - **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 29 Feb 2024 - **Updated:** 11 May 2026 - **Also known as:** DEBIAN-CVE-2021-47065, GHSA-7p9v-9x3x-2f79, UBUNTU-CVE-2021-47065 ## What is CVE-2021-47065? CVE-2021-47065 is a high-severity memory corruption vulnerability in Linux kernel, published on 29 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: rtw88: Fix array overrun in rtw_get_tx_power_params() Using a kernel with the Undefined Behaviour Sanity Checker (UBSAN) enabled, the following array overrun is logged: ================================================================================ UBSAN: array-index-out-of-bounds in /home/finger/wireless-drivers-next/drivers/net/wireless/realtek/rtw88/phy.c:1789:34 index 5 is out of range for type 'u8 [5]' CPU: 2 PID: 84 Comm: kworker/u16:3 Tainted: G O 5.12.0-rc5-00086-gd88bba47038e-dirty #651 Hardware name: TOSHIBA TECRA A50-A/TECRA A50-A, BIOS Version 4.50 09/29/2014 Workqueue: phy0 ieee80211_scan_work [mac80211] Call Trace: dump_stack+0x64/0x7c ubsan_epilogue+0x5/0x40 __ubsan_handle_out_of_bounds.cold+0x43/0x48 rtw_get_tx_power_params+0x83a/drivers/net/wireless/realtek/rtw88/0xad0 [rtw_core] ? rtw_pci_read16+0x20/0x20 [rtw_pci] ? check_hw_ready+0x50/0x90 [rtw_core] rtw_phy_get_tx_power_index+0x4d/0xd0 [rtw_core] rtw_phy_set_tx_power_level+0xee/0x1b0 [rtw_core] rtw_set_channel+0xab/0x110 [rtw_core] rtw_ops_config+0x87/0xc0 [rtw_core] ieee80211_hw_config+0x9d/0x130 [mac80211] ieee80211_scan_state_set_channel+0x81/0x170 [mac80211] ieee80211_scan_work+0x19f/0x2a0 [mac80211] process_one_work+0x1dd/0x3a0 worker_thread+0x49/0x330 ? rescuer_thread+0x3a0/0x3a0 kthread+0x134/0x150 ? kthread_create_worker_on_cpu+0x70/0x70 ret_from_fork+0x22/0x30 ================================================================================ The statement where an array is being overrun is shown in the following snippet: if (rate <= DESC_RATE11M) tx_power = pwr_idx_2g->cck_base[group]; else ====> tx_power = pwr_idx_2g->bw40_base[group]; The associated arrays are defined in main.h as follows: struct rtw_2g_txpwr_idx { u8 cck_base[6]; u8 bw40_base[5]; struct rtw_2g_1s_pwr_idx_diff ht_1s_diff; struct rtw_2g_ns_pwr_idx_diff ht_2s_diff; struct rtw_2g_ns_pwr_idx_diff ht_3s_diff; struct rtw_2g_ns_pwr_idx_diff ht_4s_diff; }; The problem arises because the value of group is 5 for channel 14. The trivial increase in the dimension of bw40_base fails as this struct must match the layout of efuse. The fix is to add the rate as an argument to rtw_get_channel_group() and set the group for channel 14 to 4 if rate <= DESC_RATE11M. This patch fixes commit fa6dfe6bff24 ("rtw88: resolve order of tx power setting routines") Weakness: CWE-129 (Improper Validation of Array Index) ## Which versions are affected by CVE-2021-47065? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2021-47065? Apply the vendor's patch. ## Is CVE-2021-47065 being exploited? There is no known exploitation of CVE-2021-47065 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-2021-47065 and fix it if it is affected. What it is: CVE-2021-47065 is a high-severity memory corruption vulnerability in Linux kernel, published on 29 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-2021-47065 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-2021-47065/ (Markdown: https://insights.sbomify.com/CVE-2021-47065/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47065 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47065 - OSV: https://osv.dev/vulnerability/CVE-2021-47065 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-47065/ Summaries are generated and may contain mistakes; the official description above is the record.