Critical severity · published Aug 15, 2026
CVE-2026-72393
eth: fbnic: don't cache shinfo across skb realloc
9.8
CVSS
0.6%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
eth: fbnic: don't cache shinfo across skb realloc
fbnic_tx_lso() calls skb_cow_head() which may reallocate the skb
including the shared info. We can't use the pointer calculated
before the call.
BUG: KASAN: slab-use-after-free in fbnic_tx_lso.isra.0+0x668/0x8e0
Read of size 4 at addr ff110000262edd98 by task swapper/5/0
Call Trace:
fbnic_tx_lso.isra.0+0x668/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
Allocated by task 8653:
__alloc_skb+0x11e/0x5f0
alloc_skb_with_frags+0xcc/0x6c0
sock_alloc_send_pskb+0x327/0x3f0
__ip_append_data+0x188b/0x47a0
ip_make_skb+0x24a/0x300
udp_sendmsg+0x14d2/0x21e0
Freed by task 0:
kfree+0x123/0x5a0
pskb_expand_head+0x36c/0xfa0
fbnic_tx_lso.isra.0+0x500/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
sch_direct_xmit+0x25b/0x1100
The buggy address belongs to the object at ff110000262edc40
which belongs to the cache skbuff_small_head of size 640
The buggy address is located 344 bytes inside of
freed 640-byte region [ff110000262edc40, ff110000262ede
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 before 83df3e2594cd78aa40b1246a19879abb4891945b; b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 before 21f304c2aae46625e050c28d979f4b9d83faa85e; b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1 before 62b68b774f06bf52e329f254f0199bc43d350ccf; 6.15 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-72393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-72393
git.kernel.org
https://git.kernel.org/stable/c/21f304c2aae46625e050c28d979f4b9d83faa85e
git.kernel.org
https://git.kernel.org/stable/c/62b68b774f06bf52e329f254f0199bc43d350ccf
git.kernel.org
https://git.kernel.org/stable/c/83df3e2594cd78aa40b1246a19879abb4891945b
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