CVE-2026-23456Network attack vector

Host interruption and disclosure via unchecked length

Published Apr 3, 2026 · Updated Apr 3, 2026

Out-of-bounds read in affected Linux Kernel branches allows remote attackers to read 1–4 bytes past a slab buffer via malformed H.323/RAS packets. In decode_int()'s CONS case, get_bits() supplies a one-to-four-byte length to get_uint() without verifying that those bytes remain after the two-bit check. Network delivery requires H.323/RAS traffic to reach the conntrack helper; no authentication or user interaction is required, and the over-read can cause limited disclosure or interrupt the host.

CVSS severity8.2
High
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Out-of-bounds read in affected Linux Kernel branches allows remote attackers to read 1–4 bytes past a slab buffer via malformed H.323/RAS packets. In decode_int()'s CONS case, get_bits() supplies a one-to-four-byte length to get_uint() without verifying that those bytes remain after the two-bit check. Network delivery requires H.323/RAS traffic to reach the conntrack helper; no authentication or user interaction is required, and the over-read can cause limited disclosure or interrupt the host.

The record

CVE
CVE-2026-23456
Published
Apr 3, 2026
Updated
Apr 3, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-125
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 3, 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=2.6.17
  2. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <1e3a3593162c96e8a8de48b1e14f60c3b57fca8a
  3. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <41b417ff73a24b2c68134992cc44c88db27f482d
  4. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <52235bf88159a1ef16434ab49e47e99c8a09ab20
  5. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <6bce72daeccca9aa1746e92d6c3d4784e71f2ebb
  6. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <774a434f8c9c8602a976b2536f65d0172a07f4d2
  7. Affected versionversion=5e35941d990123f155b02d5663e51a24f816b6f3 <fb6c3596823ec5dd09c2123340330d7448f51a59

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=2.6.17; version=5e35941d990123f155b02d5663e51a24f816b6f3 <1e3a3593162c96e8a8de48b1e14f60c3b57fca8a; version=5e35941d990123f155b02d5663e51a24f816b6f3 <41b417ff73a24b2c68134992cc44c88db27f482d; version=5e35941d990123f155b02d5663e51a24f816b6f3 <52235bf88159a1ef16434ab49e47e99c8a09ab20; version=5e35941d990123f155b02d5663e51a24f816b6f3 <6bce72daeccca9aa1746e92d6c3d4784e71f2ebb; version=5e35941d990123f155b02d5663e51a24f816b6f3 <774a434f8c9c8602a976b2536f65d0172a07f4d2; version=5e35941d990123f155b02d5663e51a24f816b6f3 <fb6c3596823ec5dd09c2123340330d7448f51a59

Published CVSS scores

8.2kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

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.

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

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read

Public exploit references

No public exploit references are available in this record.

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

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo