Skip to content
CVE PROGRAM SOURCE RECORD8.1 High

CVE-2026-98532

ipv6: do not let ipv6_find_hdr() return an offset past the packet end

Read JSON ↗CVE.org ↗
Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: ipv6: do not let ipv6_find_hdr() return an offset past the packet end ipv6_find_hdr() walks the extension header chain, skipping each header by the length that header itself declares. ipv6_optlen() returns up to 2048, and the skip is never checked against skb->len, so the offset stored in *offset can point past the end of the packet. openvswitch installs that offset as the transport header, and update_ipv6_checksum() then reads and writes the transport checksum field out of bounds: BUG: KASAN: slab-use-after-free in inet_proto_csum_replace16+0x445/0x470 Read of size 2 at addr ffff88810b754b06 by task ovs_ipv6_oob/629 CPU: 4 UID: 1000 PID: 629 Comm: ovs_ipv6_oob Tainted: G N 7.3.0-rc3+ #348 Call Trace: inet_proto_csum_replace16+0x445/0x470 set_ipv6_addr+0x3dd/0x460 do_execute_actions+0x6a3d/0x7c40 ovs_execute_actions+0xfd/0x480 ovs_packet_cmd_execute+0xc38/0xf20 genl_rcv_msg+0x59e/0x870 netlink_rcv_skb+0x18b/0x450 genl_rcv+0x2d/0x40 netlink_unicast+0x6bc/0xa20 The buggy address belongs to the object at ffff88810b754980 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 390 bytes inside of freed 704-byte region [ffff88810b754980, ffff88810b754c40) Other callers use that offset too, so bound it here rather than in one caller. Reject a header whose declared length does not fit in the packet. ipv6_find_hdr() already fails with -EBADMSG on a malformed chain, so this adds no new failure mode.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < ca96b38730e31357ef4a9d76af1336958ac670d7affected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < 531255de8971c06d5d5986f85fdc2525d707ba71affected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < 543354c6efb27eae3372a3a9674aeaa2a86e2b2caffected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < dc92cb972e86790b8078337ec41015b748b8f8e5affected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < 1c70275ca87e769e1a52abc644d61372d8c016cbaffected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < 1d42828565889632068fbc2983c34d57c66af4e0affected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < 4254d5878c320c19961dd0b8e1d0aca4800d8b7daffected
  • f8f626754ebeca613cf1af2e6f890cfde0e74d5b to < ee319bd3a0e976af5087cbe59ebc50a66f31d202affected

Linux Linux

Default version status: affected

  • 3.8affected
  • 0 to < 3.8unaffected
  • 5.10.271 to ≤ 5.10.*unaffected
  • 5.15.222 to ≤ 5.15.*unaffected
  • 6.1.189 to ≤ 6.1.*unaffected
  • 6.6.158 to ≤ 6.6.*unaffected
  • 6.12.112 to ≤ 6.12.*unaffected
  • 6.18.55 to ≤ 6.18.*unaffected
  • 7.2.9 to ≤ 7.2.*unaffected
  • 7.3 to ≤ *unaffected

References