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TI-2025-25307 Aliases CVE-2025-37961GHSA-9xjw-h43f-4f9m

ipvs: fix uninit-value for saddr in do_output_route4

Priority LOW 24CWE-908Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-908 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: ipvs: fix uninit-value for saddr in do_output_route4 syzbot reports for uninit-value for the saddr argument [1]. commit 4754957f04f5 ("ipvs: do not use random local source address for tunnels") already implies that the input value of saddr should be ignored but the code is still reading it which can prevent to connect the route. Fix it by changing the argument to ret_saddr. [1] BUG: KMSAN: uninit-value in do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 __ip_vs_get_out_rt+0x403/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:330 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118 ip_local_out net/ipv4/ip_output.c:127 [inline] ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x267/0x380 net/socket.c:727 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Uninit was created at: slab_post_alloc_hook mm/slub.c:4167 [inline] slab_alloc_node mm/slub.c:4210 [inline] __kmalloc_cache_noprof+0x8fa/0xe00 mm/slub.c:4367 kmalloc_noprof include/linux/slab.h:905 [inline] ip_vs_dest_dst_alloc net/netfilter/ipvs/ip_vs_xmit.c:61 [inline] __ip_vs_get_out_rt+0x35d/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:323 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118 ip_local_out net/ipv4/ip_output.c:127 [inline] ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x267/0x380 net/socket.c:727 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369 entry_SYSENTER_compat_after_hwframe+0x84/0x8e CPU: 0 UID: 0 PID: 22408 Comm: syz.4.5165 Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(undef) Hardware name: Google Google Compute Engi ---truncated---

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0019 8th percentileScored 2026-11-07
Fix Partial Linux (Linux): 3.11, 3.13, 3.15 +7Red Hat: 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.10.91 to before 3.11; 3.12.50 to before 3.13; 3.14.55 to before 3.15; 3.18.23 to before 3.19; 4.1.11 to before 4.23.11, 3.13, 3.15, 3.19, 4.2Patch availableCNA
LinuxLinux4.2 and later6.1.139, 6.6.91, 6.12.29, 6.14.7, 6.15Patch availableCNA
  • Linux VendorLinux Affected 3.10.91 to before 3.11; 3.12.50 to before 3.13; 3.14.55 to before 3.15; 3.18.23 to before 3.19; 4.1.11 to before 4.2 Fixed in 3.11, 3.13, 3.15, 3.19, 4.2 Patch available CNA
  • Linux VendorLinux Affected 4.2 and later Fixed in 6.1.139, 6.6.91, 6.12.29, 6.14.7, 6.15 Patch available CNA

CPE configurations NVD · 12

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*3.10.91 to before 3.11; 3.12.50 to before 3.13; 3.14.55 to before 3.15; 3.18.23 to before 3.19; 4.1.11 to before 4.2; 4.2.1 to before 6.1.139; 6.2 to before 6.6.91; 6.7 to before 6.12.29; 6.13 to before 6.14.7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:4.2:-:*:*:*:*:*:*4.2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:4.2:rc5:*:*:*:*:*:*4.2 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:4.2:rc6:*:*:*:*:*:*4.2 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:4.2:rc7:*:*:*:*:*:*4.2 rc7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:4.2:rc8:*:*:*:*:*:*4.2 rc8VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*6.15 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*6.15 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*6.15 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*6.15 rc4VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.10.91 to before 3.11; 3.12.50 to before 3.13; 3.14.55 to before 3.15; 3.18.23 to before 3.19; 4.1.11 to before 4.2; 4.2.1 to before 6.1.139; 6.2 to before 6.6.91; 6.7 to before 6.12.29; 6.13 to before 6.14.7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:4.2:-:*:*:*:*:*:* Versions 4.2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:4.2:rc5:*:*:*:*:*:* Versions 4.2 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:4.2:rc6:*:*:*:*:*:* Versions 4.2 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:4.2:rc7:*:*:*:*:*:* Versions 4.2 rc7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:4.2:rc8:*:*:*:*:*:* Versions 4.2 rc8 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:* Versions 6.15 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:* Versions 6.15 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:* Versions 6.15 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:* Versions 6.15 rc4 Vulnerable ·Linux
Show 2 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:6.15:rc5:*:*:*:*:*:*6.15 rc5VulnerableLinux
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:6.15:rc5:*:*:*:*:*:* Versions 6.15 rc5 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Linux (Linux) Fixed in 3.11, 3.13, 3.15, 3.19, 4.2
  • Fix · CNA Linux (Linux) Fixed in 6.1.139, 6.6.91, 6.12.29, 6.14.7, 6.15

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-37961
  2. 2026-10-03 Alias added: GHSA-9xjw-h43f-4f9m
  3. 2026-11-05 CISA SSVC decision points changed

References

Patch 5

Advisory 1

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences