High severity · published Feb 18, 2022
CVE-2021-20322
A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP…
7.4
CVSS
6.9%
EPSS
No
On KEV
Description
A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)6.9% · higher than 94% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
4.15 before 4.19.215; 4.20 before 5.4.157; 5.5 before 5.10.62; 5.11 before 5.13.14 · source: NVD
AI
Active IQ Unified Manager · Netapp
All versions, or not specified · source: NVD
AA
Aff A700s Firmware · Netapp
All versions, or not specified · source: NVD
AB
Aff Baseboard Management Controller Firmware · Netapp
All versions, or not specified · source: NVD
CC
Communications Cloud Native Core Binding Support Function · Oracle
22.1.3 · source: NVD
CC
Communications Cloud Native Core Network Exposure Function · Oracle
22.1.1 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
22.2.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
ES
E-series Santricity OS Controller · Netapp
11.0 through 11.70.1 · source: NVD
FB
Fas Baseboard Management Controller Firmware · Netapp
All versions, or not specified · source: NVD
FE
Fedora · Fedoraproject
34 · source: NVD
HF
H300e Firmware · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20322
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20322
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2014230
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.15-rc6&id=4785305c05b25a242e5314cc821f54ade4c18810
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.15-rc6&id=6457378fe796815c973f631a1904e147d6ee33b1
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/ipv4/route.c?h=v5.15-rc6&id=67d6d681e15b578c1725bad8ad079e05d1c48a8e
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/ipv6/route.c?h=v5.15-rc6&id=a00df2caffed3883c341d5685f830434312e4a43
Mailing List
https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
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