CVE-2025-21820 — Improper Locking in Linux

CWE-667 — Improper LockingCWE-833 — Deadlock58 documents7 sources
Severity
5.5MEDIUMNVD
OSV8.8OSV7.8OSV7.1OSV5.9
EPSS
0.0%
top 98.70%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
8
LinuxLinux KernelDebian Linux+5 more
Timeline
PublishedFeb 27
Latest updateSep 3

Description

In the Linux kernel, the following vulnerability has been resolved: tty: xilinx_uartps: split sysrq handling lockdep detects the following circular locking dependency: CPU 0 CPU 1 ========================== ============================ cdns_uart_isr() printk() uart_port_lock(port) console_lock() cdns_uart_console_write() if (!port->sysrq) uart_port_lock(port) uart_handle_break() port->sysrq = ... uart_handle_sysrq_char() printk() console_lock() The fixed commit attempts to avoid this situati…

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitability: 1.8 | Impact: 3.6

Affected Packages10 packages

▶NVDlinux/linux_kernel4.6 — 6.1.129+3
▶Debianlinux/linux_kernel< 6.1.129-1+2
▶Ubuntulinux/linux_kernel< 5.15.0-140.150+1

Patches

Patch: git.kernel.org ↗Patch: git.kernel.org ↗Patch: git.kernel.org ↗

🔴Vulnerability Details

28
OSV
linux-azure, linux-azure-6.8, linux-azure-nvidia vulnerabilities↗2025-09-03
▶
OSV
linux-raspi vulnerabilities↗2025-07-24
▶
OSV
linux-raspi-realtime vulnerabilities↗2025-07-24
▶
OSV
linux-gcp, linux-gcp-6.8 vulnerabilities↗2025-07-22
▶
OSV
linux-aws-6.8, linux-gke, linux-gkeop, linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency, linux-oracle, linux-oracle-6.8 vulnerabilities↗2025-07-22
▶

📋Vendor Advisories

29
Ubuntu
Linux kernel (Azure) vulnerabilities↗2025-09-03
▶
Ubuntu
Linux kernel (Raspberry Pi Real-time) vulnerabilities↗2025-07-24
▶
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities↗2025-07-24
▶
Ubuntu
Linux kernel (GCP) vulnerabilities↗2025-07-22
▶
Ubuntu
Linux kernel vulnerabilities↗2025-07-22
▶