CVE-2023-53192Network attack vector

Kernel panic via signed VXLAN nexthop hash

Published Sep 15, 2025 · Updated Sep 15, 2025

Out-of-bounds access in Linux kernel 5.8 through 6.5-rc4 allows remote attackers to crash hosts through VXLAN overlay traffic. vxlan_xmit_nh passes skb_get_hash()'s 32-bit value to nexthop code expecting a 31-bit signed value; an MSB-set hash becomes negative and indexes outside nh_buckets[]. Reachability requires a VXLAN FDB backed by a resilient nexthop group, after which ordinary unauthenticated overlay traffic can trigger a kernel panic.

CVSS severity9.8
Critical
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds access in Linux kernel 5.8 through 6.5-rc4 allows remote attackers to crash hosts through VXLAN overlay traffic. vxlan_xmit_nh passes skb_get_hash()'s 32-bit value to nexthop code expecting a 31-bit signed value; an MSB-set hash becomes negative and indexes outside nh_buckets[]. Reachability requires a VXLAN FDB backed by a resilient nexthop group, after which ordinary unauthenticated overlay traffic can trigger a kernel panic.

The record

CVE
CVE-2023-53192
Published
Sep 15, 2025
Updated
Sep 15, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-190, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <0756384fb1bd38adb2ebcfd1307422f433a1d772
  2. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <23c195ce6f4aec86e1c9e1ea1c800381c4b465c7
  3. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <32ef2c0c6cf11a076f0280a7866b9abc47821e19
  4. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <7b8717658dff8b471cbfc124bf9b5ca4229579ed
  5. Affected versionversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <c650597647ecb318d02372277bdfd866c6829f78
  6. Affected versionversion=5.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1274e1cc42264d4e629841e4f182795cb0becfd2 <0756384fb1bd38adb2ebcfd1307422f433a1d772; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <23c195ce6f4aec86e1c9e1ea1c800381c4b465c7; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <32ef2c0c6cf11a076f0280a7866b9abc47821e19; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <7b8717658dff8b471cbfc124bf9b5ca4229579ed; version=1274e1cc42264d4e629841e4f182795cb0becfd2 <c650597647ecb318d02372277bdfd866c6829f78; version=5.8

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.0Red HatCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:H/A:H
9.8Linux kernel CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

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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-190Integer Overflow or Wraparound
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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