CVE-2026-53236
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: tcp: restrict SO_ATTACH_FILTER to priv users This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets to users with CAP_NET_ADMIN capability. This blocks potential side-channel attack where an unprivileged application attaches a filter to leak TCP sequence/acknowledgment numbers.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-25 09:16:41.493000
Last modified
2026-11-06 17:18:15.170000
View original CVE JSON
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"published": "2026-06-25T09:16:41.493",
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"vulnStatus": "Modified",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: restrict SO_ATTACH_FILTER to priv users\n\nThis patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets\nto users with CAP_NET_ADMIN capability.\n\nThis blocks potential side-channel attack where an unprivileged application\nattaches a filter to leak TCP sequence/acknowledgment numbers."
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