Unknown

CVE-2026-80742 — af_packet: Don't send zero-byte data in tpacket_snd().

In the Linux kernel, the following vulnerability has been resolved: af_packet: Don't send zero-byte data in tpacket_snd(). syzbot reported a WARNING in __dev_queue_xmit() triggered via tpacket_snd(): skb_assert_len WARNING: at include/linux/skbuff.h:2753 skb_assert_len WARNING: at __dev_queue_xmit+0x21bc/0x4970 net/core/dev.c:4781 Call Trace: <TASK> dev_queue_xmit include/linux/netdevice.h:3448 [inline] packet_xmit+0x243/0x310 net/packet/af_packet.c:276 tpacket_snd net/packet/af_packet.c:2907 [inline] packet_sendmsg+0x28d6/0x4eb0 net/packet/af_packet.c:3134 When sending 0-byte packets via TPACKET ring buffer on devices with no hard header (e.g. dev->hard_header_len == 0), tpacket_fill_skb() populates an skb with skb->len == 0 and returns 0. tpacket_snd() then forwards this empty skb to packet_xmit(), causing __dev_queue_xmit() to hit skb_assert_len(skb). Similar checks exist in packet_snd() via commit dc633700f00f ("net/af_packet: check len when min_header_len equals to 0") and in packet_sendmsg_spkt() via commit 6a341729fb31 ("af_packet: Don't send zero-byte data in packet_sendmsg_spkt()."). Return -EINVAL in tpacket_fill_skb() when skb->len is zero to reject zero-length packets in tpacket_snd().

Published Sep 3, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.18%

ahead of 7% of scored CVEs · Oct 26, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < dde212f8622f5cb36223fff1ebd6e6f2a3dc61fe≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 80a702964467b998d254f16cc61c2c9a20540c9d≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 7521e691c7c4f2231634c95053281ac888d1f452≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 1fc70b3d513bafb16b17540178870ef46e81c0bb≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 3fa110f9e2ea96f567f2194c673c4bc327640111≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 98c5914d6b7bd4b4675535908e57dea31f1efd6a≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < f09ac5682f1bb67981fcb6ead4d3cfe439225876≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and < 6bcd76c134c55c697148acb5c0194e9666abdf84 and 1 more version 2.6.12	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 26, 2026 · 11 reading(s) · max 0.18%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 3, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/f09ac5682f1bb67981fcb6ead4d3cfe439225876
NIST National Vulnerability Database
git.kernel.org/stable/c/98c5914d6b7bd4b4675535908e57dea31f1efd6a
NIST National Vulnerability Database
git.kernel.org/stable/c/1fc70b3d513bafb16b17540178870ef46e81c0bb
NIST National Vulnerability Database
git.kernel.org/stable/c/7521e691c7c4f2231634c95053281ac888d1f452
NIST National Vulnerability Database
git.kernel.org/stable/c/80a702964467b998d254f16cc61c2c9a20540c9d
NIST National Vulnerability Database
git.kernel.org/stable/c/3fa110f9e2ea96f567f2194c673c4bc327640111
NIST National Vulnerability Database
git.kernel.org/stable/c/dde212f8622f5cb36223fff1ebd6e6f2a3dc61fe
NIST National Vulnerability Database
git.kernel.org/stable/c/6bcd76c134c55c697148acb5c0194e9666abdf84
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 1d
Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 1d
Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 1d
Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 1d
Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 1d
Unknown CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-80742 is "af_packet: Don't send zero-byte data in tpacket_snd().", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.18% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.