cbcvebase.
CVE-2025-68813
published 2026-01-13

CVE-2025-68813: In the Linux kernel, the following vulnerability has been resolved: ipvs: fix ipv4 null-ptr-deref in route error path The IPv4 code path in…

PriorityP421high7.8
EPSS
0.17%
6.9th percentile
In the Linux kernel, the following vulnerability has been resolved: ipvs: fix ipv4 null-ptr-deref in route error path The IPv4 code path in __ip_vs_get_out_rt() calls dst_link_failure() without ensuring skb->dev is set, leading to a NULL pointer dereference in fib_compute_spec_dst() when ipv4_link_failure() attempts to send ICMP destination unreachable messages. The issue emerged after commit ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure") started calling __ip_options_compile() from ipv4_link_failure(). This code path eventually calls fib_compute_spec_dst() which dereferences skb->dev. An attempt was made to fix the NULL skb->dev dereference in commit 0113d9c9d1cc ("ipv4: fix null-deref in ipv4_link_failure"), but it only addressed the immediate dev_net(skb->dev) dereference by using a fallback device. The fix was incomplete because fib_compute_spec_dst() later in the call chain still accesses skb->dev directly, which remains NULL when IPVS calls dst_link_failure(). The crash occurs when: 1. IPVS processes a packet in NAT mode with a misconfigured destination 2. Route lookup fails in __ip_vs_get_out_rt() before establishing a route 3. The error path calls dst_link_failure(skb) with skb->dev == NULL 4. ipv4_link_failure() → ipv4_send_dest_unreach() → __ip_options_compile() → fib_compute_spec_dst() 5. fib_compute_spec_dst() dereferences NULL skb->dev Apply the same fix used for IPv6 in commit 326bf17ea5d4 ("ipvs: fix ipv6 route unreach panic"): set skb->dev from skb_dst(skb)->dev before calling dst_link_failure(). KASAN: null-ptr-deref in range [0x0000000000000328-0x000000000000032f] CPU: 1 PID: 12732 Comm: syz.1.3469 Not tainted 6.6.114 #2 RIP: 0010:__in_dev_get_rcu include/linux/inetdevice.h:233 RIP: 0010:fib_compute_spec_dst+0x17a/0x9f0 net/ipv4/fib_frontend.c:285 Call Trace: spec_dst_fill net/ipv4/ip_options.c:232 spec_dst_fill net/ipv4/ip_options.c:229 __ip_options_compile+0x13a1/0x17d0 net/ipv4/ip_options.c:330 ipv4_send_dest_unreach net/

Affected

63 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
debianlinux-6.1< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 3.18.139 < 3.193.19
linuxlinux>= 4.14.114 < 4.154.15
linuxlinux>= 4.19.37 < 4.204.20
linuxlinux>= 4.4.179 < 4.54.5
linuxlinux>= 4.9.171 < 4.104.10
linuxlinux>= 5.0.10 < 5.15.1
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < dd72a93c80408f06327dd2d956eb1a656d0b5903dd72a93c80408f06327dd2d956eb1a656d0b5903
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < 312d7cd88882fc6cadcc08b02287497aaaf94bcd312d7cd88882fc6cadcc08b02287497aaaf94bcd
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < cdeff10851c37a002d87a035818ebd60fdb74447cdeff10851c37a002d87a035818ebd60fdb74447
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < 4729ff0581fbb7ad098b6153b76b6f5aac94618a4729ff0581fbb7ad098b6153b76b6f5aac94618a
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < 25ab24df31f7af843c96a38e0781b9165216e1a825ab24df31f7af843c96a38e0781b9165216e1a8
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < 689a627d14788ad772e0fa24c2e57a23dbc7ce90689a627d14788ad772e0fa24c2e57a23dbc7ce90
linuxlinux>= ed0de45a1008991fdaa27a0152befcb74d126a8b < ad891bb3d079a46a821bf2b8867854645191bab0ad891bb3d079a46a821bf2b8867854645191bab0
linuxlinux_kernel>= 0 < 5.10.249-15.10.249-1
linuxlinux_kernel>= 0 < 6.1.162-16.1.162-1
linuxlinux_kernel>= 0 < 6.12.69-16.12.69-1

CVSS provenance

osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_redhat5.5LOW
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