# CVE-2021-47633: linux: In the Linux kernel, the following vulnerability has been resolved:  ath5k: fix OOB in ath5k_eeprom_read_pcal_info_51...

CVE-2021-47633 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47633, released February 26, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-47633
- Priority: High
- CVSS: 7.1 (high)
- EPSS: 0.0026
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 26, 2025

## Description

In the Linux kernel, the following vulnerability has been resolved:  ath5k: fix OOB in ath5k_eeprom_read_pcal_info_5111  The bug was found during fuzzing. Stacktrace locates it in ath5k_eeprom_convert_pcal_info_5111. When none of the curve is selected in the loop, idx can go up to AR5K_EEPROM_N_PD_CURVES. The line makes pd out of bound. pd = &chinfo[pier].pd_curves[idx];  There are many OOB writes using pd later in the code. So I added a sanity check for idx. Checks for other loops involving AR5K_EEPROM_N_PD_CURVES are not needed as the loop index is not used outside the loops.  The patch is NOT tested with real device.  The following is the fuzzing report  BUG: KASAN: slab-out-of-bounds in ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k] Write of size 1 at addr ffff8880174a4d60 by task modprobe/214  CPU: 0 PID: 214 Comm: modprobe Not tainted 5.6.0 #1 Call Trace:  dump_stack+0x76/0xa0  print_address_description.constprop.0+0x16/0x200  ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]  ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]  __kasan_report.cold+0x37/0x7c  ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]  kasan_report+0xe/0x20  ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]  ? apic_timer_interrupt+0xa/0x20  ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]  ? ath5k_pci_eeprom_read+0x228/0x3c0 [ath5k]  ath5k_eeprom_init+0x2513/0x6290 [ath5k]  ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]  ? usleep_range+0xb8/0x100  ? apic_timer_interrupt+0xa/0x20  ? ath5k_eeprom_read_pcal_info_2413+0x2f20/0x2f20 [ath5k]  ath5k_hw_init+0xb60/0x1970 [ath5k]  ath5k_init_ah+0x6fe/0x2530 [ath5k]  ? kasprintf+0xa6/0xe0  ? ath5k_stop+0x140/0x140 [ath5k]  ? _dev_notice+0xf6/0xf6  ? apic_timer_interrupt+0xa/0x20  ath5k_pci_probe.cold+0x29a/0x3d6 [ath5k]  ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]  ? mutex_lock+0x89/0xd0  ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]  local_pci_probe+0xd3/0x160  pci_device_probe+0x23f/0x3e0  ? pci_device_remove+0x280/0x280  ? pci_device_remove+0x280/0x280  really_probe+0x209/0x5d0

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.17.3-1 | [DEBIAN-CVE-2021-47633](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47633.md) | Feb 26, 2025 |
| Linux | linux Debian 13.5 (trixie) | 5.17.3-1 | [DEBIAN-CVE-2021-47633](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47633.md) | Feb 26, 2025 |
| Linux | linux Debian 14 | 5.17.3-1 | [DEBIAN-CVE-2021-47633](https://patchblox.com/security/data/fix/linux/debian-cve-2021-47633.md) | Feb 26, 2025 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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