nfc: llcp: reject PDUs shorter than the LLCP header
Summary
| CVE | CVE-2026-80798 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-04 16:18:06 UTC |
| Updated | 2026-09-04 16:18:06 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: nfc: llcp: reject PDUs shorter than the LLCP header Every LLCP PDU begins with a two-byte header (DSAP/SSAP + PTYPE), but the receive path never checked that a frame is at least LLCP_HEADER_SIZE bytes before parsing it. nfc_llcp_rx_skb() reads the header via nfc_llcp_ptype()/nfc_llcp_dsap()/ nfc_llcp_ssap(), which dereference pdu->data[0] and pdu->data[1], and a CONNECT or CC PDU then computes tlv_array_len = skb->len - LLCP_HEADER_SIZE; as a size_t and hands it to the TLV walk. When the frame is shorter than the header the subtraction wraps to a huge value and the walk runs far past the buffer, an out-of-bounds read. A nearby NFC device can reach this without authentication; LLCP link activation happens automatically after NFC-DEP. Guard the common receive choke point __nfc_llcp_recv(), shared by both the target (nfc_llcp_data_received()) and initiator (nfc_llcp_recv()) paths, so a short skb is dropped before the rx_work worker parses it. Use pskb_may_pull() rather than a skb->len test so the two header bytes are guaranteed to sit in the skb linear area even for a non-linear skb, matching how the sibling NCI and HCI receive paths validate their headers. Reproduced with a KFENCE out-of-bounds read via /dev/virtual_nci on linux-next. Found by 0sec automated security-research tooling (https://0sec.ai). |
Risk And Classification
EPSS: 0.002340000 probability, percentile 0.142170000 (date 2026-09-07)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a e6ec76a68dce04884dfeccfe5a5f0e9f67c0ec82 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a f36cffea24bf3e2cc29a00d4b51dbcadc087d810 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a a7b9b449f5a5132221fff6adc11a9431ab8cd914 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a 3793d768b40f38bb97265dd5b9a8b8655c4e1b1d git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a eab47618e282602197db287ecbd1b09d356a2515 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a e969e98410051b1ef8cc318bfe0c7e3f24ec766d git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a ae5f20f5842f440b72d030e3a34fe182dd8eae42 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a d3d90243393c48146911c67fd3792b549d21d9e6 git | Not specified |
| CNA | Linux | Linux | affected d646960f7986fefb460a2b062d5ccc8ccfeacc3a 95674f506c6376d6722a23144c9acd26609771ed git | Not specified |
| CNA | Linux | Linux | affected 3.3 | Not specified |
| CNA | Linux | Linux | unaffected 3.3 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.267 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.218 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.185 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.154 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.106 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.47 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.11 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.1 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3-rc1 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/95674f506c6376d6722a23144c9acd26609771ed | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/d3d90243393c48146911c67fd3792b549d21d9e6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/f36cffea24bf3e2cc29a00d4b51dbcadc087d810 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ae5f20f5842f440b72d030e3a34fe182dd8eae42 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/eab47618e282602197db287ecbd1b09d356a2515 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e969e98410051b1ef8cc318bfe0c7e3f24ec766d | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e6ec76a68dce04884dfeccfe5a5f0e9f67c0ec82 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/a7b9b449f5a5132221fff6adc11a9431ab8cd914 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/3793d768b40f38bb97265dd5b9a8b8655c4e1b1d | 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.