high CVSS 7.1

CVE-2023-52598·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: s390/ptrace: handle setting of fpc register correctly If the content of the floating point control (fpc) register of a traced process is modified with the ptrace interface the new value is tested for validity by temporarily loading it into the fpc register. This may lead to corruption of the fpc register of the tracing process: if an interrupt happens while the value is temporarily loaded into the fpc register, and within interrupt context floating point or vector registers are used, the current fp/vx registers are saved with save_fpu_regs() assuming they belong to user space and will be loaded into fp/vx registers when returning to user space. test_fp_ctl() restores the original user space fpc register value, however it will be discarded, when returning to user space. In result the tracer will incorrectly continue to run with the value that was supposed to be used for the traced process. Fix this by saving fpu register contents with save_fpu_regs() before using test_fp_ctl().

Severity
high
Software
Kernel
Fixed in
6.7.4
Published
2024-03-06

Affected versions

From: 6.7

Until: 6.7.4

Fixed in: 6.7.4

How to fix this CVE

Update your Linux kernel to version 6.7.4 or later to resolve a ptrace register corruption vulnerability on s390 systems. This flaw could allow a tracing process to have its floating-point control register corrupted when debugging another process, leading to data integrity issues. Apply the kernel update immediately and reboot your system to activate the patched version.

sudo dnf update kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r
  2. Verify if your system is s390-based (the vulnerability only affects s390 architecture): uname -m
  3. If running kernel 6.7.0 through 6.7.3 on s390, your system is vulnerable
  4. After patching, confirm the new kernel version is active: uname -r (should show 6.7.4 or later)

FAQ

What is CVE-2023-52598?

CVE-2023-52598 is a kernel vulnerability in s390 ptrace handling where temporarily loading a floating-point control register value for validation can corrupt the tracing process's FPC register if an interrupt occurs during the test operation. This occurs because the interrupt handler may save and discard the original FPC value.

Is CVE-2023-52598 being actively exploited?

No, there are no known active exploits or evidence of exploitation in the wild for this vulnerability.

What versions of Kernel are affected by CVE-2023-52598?

Linux kernel versions 6.7.0 through 6.7.3 are vulnerable. Kernel 6.7.4 and later include the fix.

How do I check if my server is vulnerable to CVE-2023-52598?

Run 'uname -r' to check your kernel version and 'uname -m' to verify if you're on s390 architecture. If you see kernel 6.7.0-6.7.3 on s390, your system is vulnerable.

Does Defensia detect CVE-2023-52598?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2023-52598 will appear in your dashboard with remediation steps.

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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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