Critical severity · published Sep 16, 2026
CVE-2026-90049
net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
9.3
CVSS
0.2%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy() skb_zerocopy() copies frags from @from into @to. On an skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive operation on the source skb the copy helper does not own. That completes @from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the SKBFL_SHARED_FRAG page-ownership marker. Both callers already report the failure on their own drop path. nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost by dropping it here. On Open vSwitch's OVS_ACTION_ATTR_USERSPACE path the skb is not freed on this error: do_execute_actions() ignores output_userspace()'s return value and, unless the upcall was the last action, keeps forwarding the same skb through the flow's remaining actions. The uarg is completed while that skb is still in flight, telling the producer its buffers are free, and SKBFL_SHARED_FRAG is cleared on an skb the rest of the stack still handles. That flag is what makes esp_input() call skb_cow_data() instead of decrypting in place, so a later local ESP delivery can decrypt over frags the skb does not own privately. Leave error reporting to the callers.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
36d5fe6a000790f56039afe26834265db0a3ad4c before 849bdb83123760a865bcb2970127f4c0b9423ba3; 36d5fe6a000790f56039afe26834265db0a3ad4c before fb10e0e9b220a2eed08931a60dbaad9a2370c908; 36d5fe6a000790f56039afe26834265db0a3ad4c before 767ec2a65cc022d303b0c9c12811e7db22057341; 36d5fe6a000790f56039afe26834265db0a3ad4c before 8069643ae64dfdf634b6c78c7f622e5323031436; 36d5fe6a000790f56039afe26834265db0a3ad4c before 04dd250a78e268af3e7124beb1dc10ec1dd88d60; 36d5fe6a000790f56039afe26834265db0a3ad4c before a13b1e80e5015cd732440b475c0ef443dc4a2157; +7 more · source: vendor