Description
In the Linux kernel, the following vulnerability has been resolved: llc: fix skb UAF and leaks on llc_mac_hdr_init() failure In llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(), if llc_mac_hdr_init() fails, kfree_skb(skb) is called instead of kfree_skb(nskb). This leaks the newly allocated nskb, reads from the freed skb via LLC_I_GET_NR(pdu), and double-frees skb when llc_conn_state_process() drops its reference. In llc_sap_action_send_xid_r() and llc_sap_action_send_test_r(), nskb is leaked if llc_mac_hdr_init() returns an error. Free nskb in all three error paths.
References8
- git.kernel.org/stable/c/060f827aa3dc47939ee306da715cd6700d129616
- git.kernel.org/stable/c/41dcae82bece9f106b4dff0ee777bba8d157c8a8
- git.kernel.org/stable/c/72f9dd522f8d6c5a00be9695c7bb74631eb5069e
- git.kernel.org/stable/c/8b855b645841b5a04e20339a22bb6d593c9b790d
- git.kernel.org/stable/c/b859ba18b5a1067f71db5618c6a4a70d55fa308b
- git.kernel.org/stable/c/cb3528ad8bb46fa6252f5d14ced7febddc18515d
- git.kernel.org/stable/c/d360b31f1a3666579422872aa7d1a751e20b76f9
- git.kernel.org/stable/c/fec0fe6838a7f45175667701fb51abb23a6ffb1e
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 24 · as of 10 November 2026
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