ipv6: do not let ipv6_find_hdr() return an offset past the packet end
Summary
| CVE | CVE-2026-98532 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-18 16:17:04 UTC |
| Updated | 2026-10-24 14:16:46 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 8.1 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b ca96b38730e31357ef4a9d76af1336958ac670d7 git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b 531255de8971c06d5d5986f85fdc2525d707ba71 git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b 543354c6efb27eae3372a3a9674aeaa2a86e2b2c git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b dc92cb972e86790b8078337ec41015b748b8f8e5 git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b 1c70275ca87e769e1a52abc644d61372d8c016cb git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b 1d42828565889632068fbc2983c34d57c66af4e0 git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b 4254d5878c320c19961dd0b8e1d0aca4800d8b7d git | Not specified |
| CNA | Linux | Linux | affected f8f626754ebeca613cf1af2e6f890cfde0e74d5b ee319bd3a0e976af5087cbe59ebc50a66f31d202 git | Not specified |
| CNA | Linux | Linux | affected 3.8 | Not specified |
| CNA | Linux | Linux | unaffected 3.8 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.271 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.222 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.189 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.158 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.112 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.55 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.9 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/ca96b38730e31357ef4a9d76af1336958ac670d7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/1d42828565889632068fbc2983c34d57c66af4e0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/543354c6efb27eae3372a3a9674aeaa2a86e2b2c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/dc92cb972e86790b8078337ec41015b748b8f8e5 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/531255de8971c06d5d5986f85fdc2525d707ba71 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/4254d5878c320c19961dd0b8e1d0aca4800d8b7d | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ee319bd3a0e976af5087cbe59ebc50a66f31d202 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/1c70275ca87e769e1a52abc644d61372d8c016cb | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.