high CVSS 7.1

CVE-2021-47083·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: pinctrl: mediatek: fix global-out-of-bounds issue When eint virtual eint number is greater than gpio number, it maybe produce 'desc[eint_n]' size globle-out-of-bounds issue.

Severity
high
Software
Kernel
Fixed in
5.15.12
Published
2024-03-04

Affected versions

From: 5.11

Until: 5.15.12

Fixed in: 5.15.12

How to fix this CVE

Update your Linux kernel to version 5.15.12 or later to resolve a memory boundary violation in the Mediatek pinctrl driver that could allow local privilege escalation. This patch fixes an out-of-bounds array access when virtual EINT numbers exceed GPIO counts, preventing potential kernel memory corruption and system instability. Affected systems running kernel versions 5.11 through 5.15.11 should prioritize this update immediately.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check installed kernel version: uname -r — confirm it is 5.15.12 or later, or below 5.11
  2. Verify Mediatek pinctrl driver presence: grep -r 'CONFIG_PINCTRL_MEDIATEK' /boot/config-$(uname -r) — if output shows 'y', the vulnerable component is loaded
  3. Search kernel logs for memory access violations: sudo dmesg | grep -i 'out of bounds\|sanitizer\|global-out-of-bounds' — look for errors related to pinctrl or eint handlers
  4. Confirm patch applied: sudo cat /proc/version — verify kernel version string matches patched release (5.15.12+)

FAQ

What is CVE-2021-47083?

This vulnerability is a global buffer out-of-bounds read in the Mediatek pinctrl driver where incorrectly sized descriptor arrays can be accessed beyond their allocated memory when virtual EINT numbers exceed the actual GPIO count, leading to kernel memory exposure and potential privilege escalation.

Is CVE-2021-47083 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits have been released, though it requires local system access to trigger.

What versions of Kernel are affected by CVE-2021-47083?

Linux kernel versions 5.11 through 5.15.11 are vulnerable. Version 5.15.12 and later contain the fix.

How do I check if my server is vulnerable to CVE-2021-47083?

Run 'uname -r' and verify the kernel version is between 5.11 and 5.15.11; additionally check if Mediatek pinctrl is enabled with 'grep CONFIG_PINCTRL_MEDIATEK /boot/config-$(uname -r)'.

Does Defensia detect CVE-2021-47083?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2021-47083 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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CVE-2024-38612CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix invalid unregister error path The error path of seg6_init() is wrong in case CONFIG_IPV6_SEG6_LWTUNNEL is not defined. In that case if seg6_hmac_init() fails, the genl_unregister_family() isn't called. This issue exist since commit 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support"), and commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") replaced unregister_pernet_subsys() with genl_unregister_family() in this error path.
CVE-2024-38623CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Use variable length array instead of fixed size Should fix smatch warning: ntfs_set_label() error: __builtin_memcpy() 'uni->name' too small (20 vs 256)
CVE-2021-47548CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() The if statement: if (port >= DSAF_GE_NUM) return; limits the value of port less than DSAF_GE_NUM (i.e., 8). However, if the value of port is 6 or 7, an array overflow could occur: port_rst_off = dsaf_dev->mac_cb[port]->port_rst_off; because the length of dsaf_dev->mac_cb is DSAF_MAX_PORT_NUM (i.e., 6). To fix this possible array overflow, we first check port and if it is greater than or equal to DSAF_MAX_PORT_NUM, the function returns.

References

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