Security Bulletin
This security bulletin contains one medium risk vulnerability.
EUVDB-ID: #VU59085
Risk: Medium
CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2021-20257
CWE-ID:
CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Exploit availability: No
DescriptionThe vulnerability allows a remote user to perform a denial of service (DoS) attack.
The vulnerability exists due to infinite loop in the e1000 NIC emulator when processing transmits (tx) descriptors in process_tx_desc of QEMU. A remote user can consume all available CPU resources and cause denial of service conditions.
MitigationInstall updates from vendor's website.
Vulnerable software versionsQEMU: 6.0.0 - 6.1.0
CPE2.3https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg03595.html
https://bugzilla.redhat.com/show_bug.cgi?id=1930087
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
How the attacker can exploit this vulnerability?
The attacker would have to trick the victim to open a a specially crafted file.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.