EUVD-2026-24823
GHSA-j49f-wwvq-pvp4
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
3DescriptionNVD
In the Linux kernel, the following vulnerability has been resolved:
xfrm: iptfs: validate inner IPv4 header length in IPTFS payload
Add validation of the inner IPv4 packet tot_len and ihl fields parsed from decrypted IPTFS payloads in __input_process_payload(). A crafted ESP packet containing an inner IPv4 header with tot_len=0 causes an infinite loop: iplen=0 leads to capturelen=min(0, remaining)=0, so the data offset never advances and the while(data < tail) loop never terminates, spinning forever in softirq context.
Reject inner IPv4 packets where tot_len < ihl*4 or ihl*4 < sizeof(struct iphdr), which catches both the tot_len=0 case and malformed ihl values. The normal IP stack performs this validation in ip_rcv_core(), but IPTFS extracts and processes inner packets before they reach that layer.
AnalysisAI
Denial of service in Linux kernel IPTFS (IP Traffic Flow Security) subsystem allows local authenticated attackers to trigger an infinite loop via crafted ESP packets with malformed inner IPv4 headers containing tot_len=0. The vulnerability bypasses input validation in __input_process_payload() that should reject IPv4 packets where tot_len is less than the header length, causing the kernel to spin indefinitely in softirq context and hang the system.
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