#VU63087 Time-of-check Time-of-use (TOCTOU) Race Condition in Qualcomm products - CVE-2021-35082

Vulnerability identifier: #VU63087

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-35082

CWE-ID: CWE-367

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
MDM9206
Hardware solutions / Firmware
QCA9377
Hardware solutions / Firmware
QCA9367
Mobile applications / Mobile firmware & hardware

Vendor: Qualcomm

Description

The vulnerability allows a remote attacker to compromise the affected device.

The vulnerability exists due to race condition between PDCP and RRC tasks within NB1 component. A remote attacker can send specially crafted traffic after a valid RRC security mode command packet has been received and execute arbitrary code on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

MDM9206: All versions

QCA9367: All versions

QCA9377: All versions

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External links
https://docs.qualcomm.com/bundle/publicresource/HD-10000-1/topics/may-2022-bulletin.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.