CVE-2025-71090Network attack vector

Remote service interruption via nfsd reference leak

Published Jan 13, 2026 · Updated Jan 13, 2026

Reference leakage in Linux Kernel 6.17 allows remote attackers to exhaust NFS server resources through crafted NFSv4.1 OPEN requests. nfsd4_add_rdaccess_to_wrdeleg() overwrites fi_fds[O_RDONLY] without releasing an existing reference and aliases one nfsd_file into two fields with only one reference. An exposed read-write NFS export and repeatable READ and WRITE open sequences are sufficient to retain objects, cause open conflicts, and panic the host during nfsd teardown.

CVSS severity7.5
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reference leakage in Linux Kernel 6.17 allows remote attackers to exhaust NFS server resources through crafted NFSv4.1 OPEN requests. nfsd4_add_rdaccess_to_wrdeleg() overwrites fi_fds[O_RDONLY] without releasing an existing reference and aliases one nfsd_file into two fields with only one reference. An exposed read-write NFS export and repeatable READ and WRITE open sequences are sufficient to retain objects, cause open conflicts, and panic the host during nfsd teardown.

The record

CVE
CVE-2025-71090
Published
Jan 13, 2026
Updated
Jan 13, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 13, 2026Record 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=6.17
  2. Affected versionversion=e7a8ebc305f26cab608e59a916a4ae89d6656c5f <8072e34e1387d03102b788677d491e2bcceef6f5
  3. Affected versionversion=e7a8ebc305f26cab608e59a916a4ae89d6656c5f <c07dc84ed67c5a182273171639bacbbb87c12175

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.17; version=e7a8ebc305f26cab608e59a916a4ae89d6656c5f <8072e34e1387d03102b788677d491e2bcceef6f5; version=e7a8ebc305f26cab608e59a916a4ae89d6656c5f <c07dc84ed67c5a182273171639bacbbb87c12175

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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

T1499.004Application 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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