CVE-2025-21637 (GCVE-0-2025-21637)
Vulnerability from cvelistv5
Published
2025-01-19 10:17
Modified
2026-08-05 11:53
Severity ?
7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: udp_port: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, but that would increase the size of this fix, while 'sctp.ctl_sock' still needs to be retrieved from 'net' structure.
References
Impacted products
Vendor Product Version
Linux Linux Version: 046c052b475e7119b6a30e3483e2888fc606a2f8
Version: 046c052b475e7119b6a30e3483e2888fc606a2f8
Version: 046c052b475e7119b6a30e3483e2888fc606a2f8
Version: 046c052b475e7119b6a30e3483e2888fc606a2f8
Version: 046c052b475e7119b6a30e3483e2888fc606a2f8
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