Medium severity · published Apr 5, 2026
CVE-2026-5590
net: ip/tcp: Null pointer dereference can be triggered by a race condition
5.3
CVSS
0.2%
EPSS
No
On KEV
Description
A race condition during TCP connection teardown can cause tcp_recv() to operate on a connection that has already been released. If tcp_conn_search() returns NULL while processing a SYN packet, a NULL pointer derived from stale context data is passed to tcp_backlog_is_full() and dereferenced without validation, leading to a crash.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZE
Zephyr · zephyrproject-rtos
before 4.3.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-5590
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-5590
Exploit
https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-4vqm-pw24-g9jp
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