high CVSS 8.8 EPSS 0.40%

CVE-2026-64441·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix OOB reads in rtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr() Three IE/attribute parsing functions have missing bounds checks. rtw_get_sec_ie() and rtw_get_wapi_ie() iterate over a raw IE buffer without verifying that the header bytes (tag + length) are within the remaining buffer before reading them. Additionally, rtw_get_sec_ie() compares the 4-byte WPA OUI at cnt+2 without checking that at least 6 bytes remain, and rtw_get_wapi_ie() compares a 4-byte WAPI OUI at cnt+6 without checking that at least 10 bytes remain. rtw_get_wps_attr() reads wps_ie[0] and wps_ie+2 unconditionally at entry, before verifying that wps_ielen is large enough to contain the 6-byte WPS IE header (element_id + length + 4-byte OUI). Inside the attribute loop, get_unaligned_be16() is called on attr_ptr and attr_ptr+2 without checking that 4 bytes remain in the buffer. Add a cnt+2 bounds check before each loop body in rtw_get_sec_ie() and rtw_get_wapi_ie(), guard each multi-byte comparison with a minimum IE length requirement, add a wps_ielen < 6 early return in rtw_get_wps_attr(), and add a 4-byte bounds check in its inner loop.

Severity
high
Software
Kernel
Fixed in
7.1.4
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.40% — higher than 32% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-64441 scores 8.8 on CVSS, so a successful attack would be serious — but at 0.40%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 6.19

Until: 7.1.4

Fixed in: 7.1.4

How to fix this CVE

Update your Linux kernel to version 7.1.4 or later to patch out-of-bounds read vulnerabilities in wireless IE parsing functions. These functions lack proper bounds checking when parsing wireless information elements, potentially allowing memory disclosure or denial of service. Apply the kernel update immediately and reboot your systems to activate the fix.

sudo dnf check-update kernel && sudo dnf update kernel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check current kernel version with 'uname -r' and compare against affected range 6.19 to 7.1.4
  2. Step 2: Verify the rtl8723bs staging driver is loaded with 'lsmod | grep rtl8723bs' to confirm exposure
  3. Step 3: Search system logs for wireless scanning or connection attempts around suspicious timestamps: 'grep -i "rtl8723\|wapi\|wps" /var/log/kern.log /var/log/syslog 2>/dev/null'
  4. Step 4: After patching, confirm kernel version with 'uname -r' returns 7.1.4 or higher, then verify driver is functional with 'sudo systemctl restart networking'

FAQ

What is CVE-2026-64441?

This vulnerability consists of three separate out-of-bounds read flaws in the rtl8723bs WiFi driver's IE (Information Element) parsing functions. Missing boundary checks allow reading beyond allocated buffer limits when processing malformed wireless frames, potentially exposing sensitive kernel memory.

Is CVE-2026-64441 being actively exploited?

No, this vulnerability is not currently listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available. However, the high CVSS score of 8.8 warrants prompt patching.

What versions of Kernel are affected by CVE-2026-64441?

Linux kernel versions 6.19 through 7.1.3 are vulnerable. The fix is included in kernel version 7.1.4 and later.

How do I check if my server is vulnerable to CVE-2026-64441?

Run 'uname -r' to display your kernel version. If it shows a version between 6.19 and 7.1.3 (inclusive) and the rtl8723bs driver is loaded ('lsmod | grep rtl8723bs'), your system is vulnerable.

Does Defensia detect CVE-2026-64441?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2026-64441 will appear in your dashboard with remediation steps.

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References

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