CVE-2026-53391Network attack vector

Client panic via zero-length pNFS address

Published Jul 19, 2026 · Updated Jul 19, 2026

NULL pointer dereference in Linux Kernel NFSv4/pNFS allows remote attackers to panic clients via a crafted GETDEVICEINFO reply. nfs4_decode_mp_ds_addr accepts a zero-length r_addr from the multipath data-server body, receives a NULL buffer from xdr_stream_decode_string_dup, and passes it to strrchr. Reachability requires a pNFS flexfiles client mounted to a malicious or compromised metadata server; the resulting kernel panic interrupts the client system.

CVSS severity7.5
High
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Linux Kernel NFSv4/pNFS allows remote attackers to panic clients via a crafted GETDEVICEINFO reply. nfs4_decode_mp_ds_addr accepts a zero-length r_addr from the multipath data-server body, receives a NULL buffer from xdr_stream_decode_string_dup, and passes it to strrchr. Reachability requires a pNFS flexfiles client mounted to a malicious or compromised metadata server; the resulting kernel panic interrupts the client system.

The record

CVE
CVE-2026-53391
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 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=4.0
  2. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <012d37a568bfbb2c9686f03ade75560bc7139956
  3. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <30aae62e50b4e074a90a9a5e15246548fbdc1182
  4. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <41fe0f7b84f0cb822ae10ab08592996a592b2a25
  5. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <427ab81a811dab4bca9d19f82eec5847ae42646e
  6. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea
  7. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <76b94cbd32aacf36a641956385a852635c6802b9
  8. Affected versionversion=6b7f3cf96364eaf597940cb5c68a682894829915 <c8e4e0c701d0192a2efb6df059c0f9e19678c23d

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.0; version=6b7f3cf96364eaf597940cb5c68a682894829915 <012d37a568bfbb2c9686f03ade75560bc7139956; version=6b7f3cf96364eaf597940cb5c68a682894829915 <30aae62e50b4e074a90a9a5e15246548fbdc1182; version=6b7f3cf96364eaf597940cb5c68a682894829915 <41fe0f7b84f0cb822ae10ab08592996a592b2a25; version=6b7f3cf96364eaf597940cb5c68a682894829915 <427ab81a811dab4bca9d19f82eec5847ae42646e; version=6b7f3cf96364eaf597940cb5c68a682894829915 <6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea; version=6b7f3cf96364eaf597940cb5c68a682894829915 <76b94cbd32aacf36a641956385a852635c6802b9; version=6b7f3cf96364eaf597940cb5c68a682894829915 <c8e4e0c701d0192a2efb6df059c0f9e19678c23d

Published CVSS scores

7.5kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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.

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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-476NULL Pointer Dereference
T1499Endpoint Denial of Service

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

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Your stack

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