cbcvebase.
CVE-2026-43139
published 2026-05-06

CVE-2026-43139: In the Linux kernel, the following vulnerability has been resolved: xfrm6: fix uninitialized saddr in xfrm6_get_saddr() xfrm6_get_saddr() does not check the…

PriorityP343high8.6CVSS 3.1
AVNACLPRNUINSUCLILAH
EPSS
0.38%
30.1th percentile
In the Linux kernel, the following vulnerability has been resolved: xfrm6: fix uninitialized saddr in xfrm6_get_saddr() xfrm6_get_saddr() does not check the return value of ipv6_dev_get_saddr(). When ipv6_dev_get_saddr() fails to find a suitable source address (returns -EADDRNOTAVAIL), saddr->in6 is left uninitialized, but xfrm6_get_saddr() still returns 0 (success). This causes the caller xfrm_tmpl_resolve_one() to use the uninitialized address in xfrm_state_find(), triggering KMSAN warning: BUG: KMSAN: uninit-value in xfrm_state_find+0x2424/0xa940 xfrm_state_find+0x2424/0xa940 xfrm_resolve_and_create_bundle+0x906/0x5a20 xfrm_lookup_with_ifid+0xcc0/0x3770 xfrm_lookup_route+0x63/0x2b0 ip_route_output_flow+0x1ce/0x270 udp_sendmsg+0x2ce1/0x3400 inet_sendmsg+0x1ef/0x2a0 __sock_sendmsg+0x278/0x3d0 __sys_sendto+0x593/0x720 __x64_sys_sendto+0x130/0x200 x64_sys_call+0x332b/0x3e70 do_syscall_64+0xd3/0xf80 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable tmp.i.i created at: xfrm_resolve_and_create_bundle+0x3e3/0x5a20 xfrm_lookup_with_ifid+0xcc0/0x3770 Fix by checking the return value of ipv6_dev_get_saddr() and propagating the error.

Affected

52 ranges· showing 25
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < 4f28141786e1fe884ce42a5197ba9beed540f0ea4f28141786e1fe884ce42a5197ba9beed540f0ea
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < 6535867673bf301d52aa00593a4d1d18cc3922fa6535867673bf301d52aa00593a4d1d18cc3922fa
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < eb2ee15290af14c60b45cf2b73f5687d1d077d9beb2ee15290af14c60b45cf2b73f5687d1d077d9b
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < 719918fc88df6da023dfff370cd965151a5afd7f719918fc88df6da023dfff370cd965151a5afd7f
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < dc0abce055134cb83b0d981d31ceb20dda419787dc0abce055134cb83b0d981d31ceb20dda419787
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < c7221e7bd8fc2ef38a0b27be580d9d202281306bc7221e7bd8fc2ef38a0b27be580d9d202281306b
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < 3dcd1664ac15eee6a690daec7c4ffc59190406f73dcd1664ac15eee6a690daec7c4ffc59190406f7
linuxlinux>= a1e59abf824969554b90facd44a4ab16e265afa4 < 1799d8abeabc68ec05679292aaf6cba93b343c051799d8abeabc68ec05679292aaf6cba93b343c05
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 2.6.19 < 5.10.2525.10.252
linuxlinux_kernel>= 5.11 < 5.15.2025.15.202
linuxlinux_kernel>= 5.16 < 6.1.1656.1.165
linuxlinux_kernel>= 6.13 < 6.18.166.18.16
linuxlinux_kernel>= 6.19 < 6.19.66.19.6
linuxlinux_kernel>= 6.2 < 6.6.1286.6.128
linuxlinux_kernel>= 6.7 < 6.12.756.12.75
ubuntulinux
ubuntulinux-aws
ubuntulinux-aws-5.15
ubuntulinux-aws-6.8
ubuntulinux-aws-fips
ubuntulinux-azure-fips
ubuntulinux-fips

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
vendor_ubuntu8.8HIGH
vendor_redhat5.5MEDIUM
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