Low severity · published Jun 15, 2021
CVE-2021-3593
An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU
3.8
CVSS
0.3%
EPSS
No
On KEV
Description
An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the udp6_input() function and could occur while processing a udp packet that is smaller than the size of the 'udphdr' structure. This issue may lead to out-of-bounds read access or indirect host memory disclosure to the guest. The highest threat from this vulnerability is to data confidentiality. This flaw affects libslirp versions prior to 4.6.0.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
EL
Enterprise Linux · Redhat
8.0; 8.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
LI
Libslirp · Libslirp Project
before 4.6.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3593
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3593
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1970487
Mailing List
https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/03/msg00013.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GCKWZWY64EHTOQMLVLTSZ4AA27EWRJMH/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SGPQZFVJCFGDSISFXPCQTTBBD7QZLJKI/
Third Party Advisory
https://security.gentoo.org/glsa/202107-44
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