CVE-2026-43011
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at line 48 and returns 1 (error). This error propagates back through the call chain: x25_queue_rx_frame returns 1 | v x25_state3_machine receives the return value 1 and takes the else branch at line 278, setting queued=0 and returning 0 | v x25_process_rx_frame returns queued=0 | v x25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb) again This would free the same skb twice. Looking at x25_backlog_rcv: net/x25/x25_in.c:x25_backlog_rcv() { ... queued = x25_process_rx_frame(sk, skb); ... if (!queued) kfree_skb(skb); }
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-01 15:16:44.993000
Last modified
2026-10-19 20:17:59.927000
View original CVE JSON
{
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"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-05-01T15:16:44.993",
"lastModified": "2026-10-19T20:17:59.927",
"vulnStatus": "Modified",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/x25: Fix potential double free of skb\n\nWhen alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at\nline 48 and returns 1 (error).\nThis error propagates back through the call chain:\n\nx25_queue_rx_frame returns 1\n |\n v\nx25_state3_machine receives the return value 1 and takes the else\nbranch at line 278, setting queued=0 and returning 0\n |\n v\nx25_process_rx_frame returns queued=0\n |\n v\nx25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb)\nagain\n\nThis would free the same skb twice. Looking at x25_backlog_rcv:\n\nnet/x25/x25_in.c:x25_backlog_rcv() {\n ...\n queued = x25_process_rx_frame(sk, skb);\n ...\n if (!queued)\n kfree_skb(skb);\n}"
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