High severity · published Sep 18, 2026
CVE-2026-63448
Suricata smb: some SMB flows can cause resource exhaustion
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 7.0.17 and 8.0.6, the SMB parser can retain force-completed transactions on flows where Suricata sees payload in only one direction, including async-oneside flows, because cleanup waits for inspection in the unseen direction. The transaction creation paths in rust/src/smb can exceed the intended SMB_MAX_TX bound, and cleanup repeatedly scans the growing list. Sustained one-directional SMB traffic can therefore cause unbounded per-flow state and CPU and memory exhaustion. This issue is fixed in versions 8.0.6 and 7.0.17.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SU
suricata · OISF
>= 8.0.0, < 8.0.6; < 7.0.17 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-63448
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-63448
Patch
https://github.com/OISF/suricata/commit/755d6c3061de4d7ba97f0ed31cdc17ab8cab4476
Patch
https://github.com/OISF/suricata/commit/7ec9d72d28b9370712cf77a5b9d40d6b5db27cb4
Patch
https://github.com/OISF/suricata/commit/88adab8bd3d62912941647ab65032d5ec75c893a
Patch
https://github.com/OISF/suricata/commit/9a54a043516e644bb7b9d34117a91977f950a281
Patch
https://github.com/OISF/suricata/commit/bc39274a638d1cca2391cfa4891c8b6c255ff9ce
Patch
https://github.com/OISF/suricata/commit/c8f68b0e4f9e721dca1c9ed6e08597c6964c7ac3
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