CVE-2023-53705Network attack vector

Kernel crash via malformed IPv6 TLV length

Published Oct 22, 2025 · Updated Oct 22, 2025

Out-of-bounds read in affected Linux kernel releases allows remote attackers to crash the kernel via malformed IPv6 extension headers. ipv6_find_tlv() reads nh[offset + 1] when only one byte remains because it fetches the TLV length without first requiring two bytes. Unauthenticated network packets can reach the parser; the one-byte read is not disclosed or written back, but it can fault and cause a kernel oops.

CVSS severity8.2
High
EPSS probability0.53%
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 releases allows remote attackers to crash the kernel via malformed IPv6 extension headers. ipv6_find_tlv() reads nh[offset + 1] when only one byte remains because it fetches the TLV length without first requiring two bytes. Unauthenticated network packets can reach the parser; the one-byte read is not disclosed or written back, but it can fault and cause a kernel oops.

The record

CVE
CVE-2023-53705
Published
Oct 22, 2025
Updated
Oct 22, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 22, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 22, 2025Record 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=2.6.19
  2. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <011f47c8b8389154f996f5f69da8efc3a3beefef
  3. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <04bf69e3de435d793a203aacc4b774f8f9f2baeb
  4. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <59e656d0d4a84ea0ee9a39c6f69160a3effccc94
  5. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <878ecb0897f4737a4c9401f3523fd49589025671
  6. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <91dd8aab9c9f193210681b86b6b92840ffe74f0c
  7. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <9b92e2d0eb696d7586ba832c8854653b59887da0
  8. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <ae68c0f7edbc9a294094ce03a0aaf45aa489ce40
  9. Affected versionversion=c61a404325093250b676f40ad8f4dd00f3bcab5f <e5f82688ae10f5f386952e65e941bb8868ee54dc

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.19; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <011f47c8b8389154f996f5f69da8efc3a3beefef; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <04bf69e3de435d793a203aacc4b774f8f9f2baeb; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <59e656d0d4a84ea0ee9a39c6f69160a3effccc94; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <878ecb0897f4737a4c9401f3523fd49589025671; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <91dd8aab9c9f193210681b86b6b92840ffe74f0c; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <9b92e2d0eb696d7586ba832c8854653b59887da0; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <ae68c0f7edbc9a294094ce03a0aaf45aa489ce40; version=c61a404325093250b676f40ad8f4dd00f3bcab5f <e5f82688ae10f5f386952e65e941bb8868ee54dc

Published CVSS scores

8.2Linux CVE TeamCVSS: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

T1499.004Application or System Exploitation

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