Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/1492e3dcb2be3aa46d1963da96aa9593e4e4db5a Patch
- git.kernel.org/stable/c/a4d634ded4d3d400f115d84f654f316f249531c9 Patch
- git.kernel.org/stable/c/078d33c95bf534d37aa04269d1ae6158e20082d5
- git.kernel.org/stable/c/64b7684042246e3238464c66894e30ba30c7e851
- git.kernel.org/stable/c/9e5021a906532ca16e2aac69c0607711e1c70b1f
- git.kernel.org/stable/c/b05500444b8eb97644efdd180839a04a706be97c
- git.kernel.org/stable/c/bada48ad5b0590e318d0f79636ff62a2ef9f4955
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 8 November 2026
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