CVE-2026-98547Public exploitHinoki check available

CPU hang via packet-ring timeout integer overflow

Published Oct 18, 2026 · Updated Oct 18, 2026

Integer overflow in Linux AF_PACKET allows local users to hang CPUs via crafted TPACKET_V3 receive-ring block sizes. The prb_calc_retire_blk_tmo() function multiplies an attacker-controlled block size by eight in 32-bit arithmetic, producing a negative timeout that makes the retirement timer repeatedly fire. The maximum-rate CPU spin affects the hrtimer implementation introduced in 6.18 and requires CAP_NET_RAW, automatic timeout selection, and a suitable reported link speed, including 1 Gbps; additional rings exhaust additional CPUs until their sockets close.

CVSS severityUnavailable
Unscored
EPSS probability0.21%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Get started

Summary

What happened

Integer overflow in Linux AF_PACKET allows local users to hang CPUs via crafted TPACKET_V3 receive-ring block sizes. The prb_calc_retire_blk_tmo() function multiplies an attacker-controlled block size by eight in 32-bit arithmetic, producing a negative timeout that makes the retirement timer repeatedly fire. The maximum-rate CPU spin affects the hrtimer implementation introduced in 6.18 and requires CAP_NET_RAW, automatic timeout selection, and a suitable reported link speed, including 1 Gbps; additional rings exhaust additional CPUs until their sockets close.

The record

CVE
CVE-2026-98547
Published
Oct 18, 2026
Updated
Oct 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.2
  2. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <02afd75649a4e001031ed82153a5c39312ec0737
  3. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <218a944b9e035d4b47d59c69af6ca13319da15fb
  4. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <297acc571d5813db76b147c745b91031d5f9c960
  5. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <56d82862a0a243ac14ba11b6d7b57ddc2d064b95
  6. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <6279211e7d2456ecd195d236c9ee5e5c6fa5a17a
  7. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <b2bcc6a254d6f27823a56787668ae4ee8cdb6e71
  8. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <be1aacff399d519cc48d6b34354a54dd79041140
  9. Affected versionversion=f6fb8f100b807378fda19e83e5ac6828b638603a <eb5b3838b9200dac04bfe33483db0ee8287456fb

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3.2; version=f6fb8f100b807378fda19e83e5ac6828b638603a <02afd75649a4e001031ed82153a5c39312ec0737; version=f6fb8f100b807378fda19e83e5ac6828b638603a <218a944b9e035d4b47d59c69af6ca13319da15fb; version=f6fb8f100b807378fda19e83e5ac6828b638603a <297acc571d5813db76b147c745b91031d5f9c960; version=f6fb8f100b807378fda19e83e5ac6828b638603a <56d82862a0a243ac14ba11b6d7b57ddc2d064b95; version=f6fb8f100b807378fda19e83e5ac6828b638603a <6279211e7d2456ecd195d236c9ee5e5c6fa5a17a; version=f6fb8f100b807378fda19e83e5ac6828b638603a <b2bcc6a254d6f27823a56787668ae4ee8cdb6e71; version=f6fb8f100b807378fda19e83e5ac6828b638603a <be1aacff399d519cc48d6b34354a54dd79041140; version=f6fb8f100b807378fda19e83e5ac6828b638603a <eb5b3838b9200dac04bfe33483db0ee8287456fb

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Get started to see how Hinoki identifies affected software and validates exploitability in your environment.

Get started