Critical severity · published Oct 12, 2021
CVE-2021-3323
Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr
9.8
CVSS
0.9%
EPSS
No
On KEV
Description
Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions >= >=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZE
Zephyr · Zephyrproject
2.4.0 before 2.5.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3323
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3323
Exploit
http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc
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