All vulnerabilities
CVE-2026-100071

Linux: net: hsr: free learned nodes on device setup failure

Linux LinuxOperating systems
Open in ThreatlineRecord JSON
CVSS
NoneNot scored
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.11%Chance of exploitation activity in the next 30 days, higher than 1% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in0a340ffd96943a49a78e367efac9517ca767d99bAlso 65702339b3e9fd792f65d4b740928798194d86ce, 49b01f2939abc676a6f9a118f07a10110ee5f683 and 1 moreCVE List
Published25 Sep 2026Updated 19 Oct 2026CVE List

What fixes it

  • 0a340ffd96943a49a78e367efac9517ca767d99bLinuxCVE List
  • 65702339b3e9fd792f65d4b740928798194d86ceLinuxCVE List
  • 49b01f2939abc676a6f9a118f07a10110ee5f683LinuxCVE List
  • 7f16289b91eb316f170a6bd22d32e6c632f6a5b6LinuxCVE List

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

In the Linux kernel, the following vulnerability has been resolved:

net: hsr: free learned nodes on device setup failure

hsr_dev_finalize() can fail after a lower-device RX handler has already been registered (slave A is added before the failable slave B and interlink adds). RX handlers run in softirq regardless of the master's state, so frames received in that window can learn dynamic nodes into node_db, and the error unwind never releases them.

Free both owned dynamic databases in the unwind, mirroring hsr_dellink(). proxy_node_db is provably empty on every current error exit (only interlink RX feeds it, and the interlink add is the last failable step) and is freed for symmetry. The order is safe: hsr_del_port() unregisters each RX handler with synchronize_net() before hsr_del_nodes() runs, which removes remaining entries with list_del_rcu() and defers their release with call_rcu() for readers already under RCU.

Text from CVE List

Affected versions 14

  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before e691eee886871b933d772ffc76d66c80b4c0a25eCVE List
  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before 0a340ffd96943a49a78e367efac9517ca767d99bCVE List
  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before f7289e3492f2694dccd3d79287e0e31879b58650CVE List
  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before 65702339b3e9fd792f65d4b740928798194d86ceCVE List
  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before 49b01f2939abc676a6f9a118f07a10110ee5f683CVE List
  • Linuxaffected: 81ba6afd6e6443d2bf4bf40f16df1f1f91c603f8 before 7f16289b91eb316f170a6bd22d32e6c632f6a5b6CVE List
  • Linuxaffected: 3.17CVE List
  • Linuxunaffected: all versions before 3.17CVE List
  • Linuxunaffected: 6.1.188 through 6.1.*CVE List
  • Linuxunaffected: 6.6.157 through 6.6.*CVE List
  • Linuxunaffected: 6.12.110 through 6.12.*CVE List
  • Linuxunaffected: 6.18.52 through 6.18.*CVE List
  • Linuxunaffected: 7.2.6 through 7.2.*CVE List
  • Linuxunaffected: 7.3CVE List

References 6