Yüksek CVSS 7.1
CVE-2026-52942: Linux Kernel: sınır dışı okuma
Açıklama (NVD)
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_log: validate MAC header was set before dumping it The fallback path of dump_mac_header() guards the MAC header access only with "skb->mac_header != skb->network_header", without checking skb_mac_header_was_set(). When the MAC header is unset, mac_header is 0xffff, so the test passes and skb_mac_header(skb) returns skb->head + 0xffff, ~64 KiB past the buffer; the loop then reads dev->hard_header_len bytes out of bounds into the kernel log. This is reachable via the netdev logger: nf_log_unknown_packet() calls dump_mac_header() unconditionally, and an skb sent through AF_PACKET with PACKET_QDISC_BYPASS reaches the egress hook with mac_header still unset (__dev_queue_xmit(), which would reset it, is bypassed). Add the skb_mac_header_was_set() check the ARPHRD_ETHER path already uses, and replace the open-coded MAC header length test with skb_mac_header_len(). Only skbs with an unset MAC header are affected; valid ones are dumped as before. BUG: KASAN: slab-out-of-bounds in dump_mac_header (net/netfilter/nf_log_syslog.c:831) Read of size 1 at addr ffff88800ea49d3f by task exploit/148 Call Trace: kasan_report (mm/kasan/report.c:595) dump_mac_header (net/netfilter/nf_log_syslog.c:831) nf_log_netdev_packet (net/netfilter/nf_log_syslog.c:938 net/netfilter/nf_log_syslog.c:963) nf_log_packet (net/netfilter/nf_log.c:260) nft_log_eval (net/netfilter/nft_log.c:60) nft_do_chain (net/netfilter/nf_tables_core.c:285) nft_do_chain_netdev (net/netfilter/nft_chain_filter.c:307) nf_hook_slow (net/netfilter/core.c:619) nf_hook_direct_egress (net/packet/af_packet.c:257) packet_xmit (net/packet/af_packet.c:280) packet_sendmsg (net/packet/af_packet.c:3114) __sys_sendto (net/socket.c:2265)
Özet bilgiler
- Ürün
- Linux Linux Kernel
- CVSS v3.1
- 7.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H - EPSS
- %0,13 (yüzdelik 3)
- CWE
- CWE-125
- Yama
- Mevcut
Etkilenen sürümler
| Ürün | Başlangıç | Bitiş | Düzeltildi |
|---|---|---|---|
| linux-linux-kernel | 2.6.36 | — | 5.15.210 |
| linux-linux-kernel | 5.16 | — | 6.1.176 |
| linux-linux-kernel | 6.2 | — | 6.6.143 |
| linux-linux-kernel | 6.7 | — | 6.12.94 |
| linux-linux-kernel | 6.13 | — | 6.18.36 |
| linux-linux-kernel | 6.19 | — | 7.0.13 |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |