CVE-2026-53689Network attack vector

Client crash or code execution via unchecked length

Published Jun 10, 2026 · Updated Jun 10, 2026

Integer overflow in libnfs 6.0.2 and earlier allows remote attackers controlling an NFS server to crash or execute code in clients. libnfs_zdr_string decodes a server-supplied 32-bit string size, then casts it to a signed integer during a position bounds check without first limiting it to the input buffer. A client application must connect to the crafted server; the resulting overflow can corrupt the client process, causing a crash or arbitrary code execution.

CVSS severity7.1
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

Integer overflow in libnfs 6.0.2 and earlier allows remote attackers controlling an NFS server to crash or execute code in clients. libnfs_zdr_string decodes a server-supplied 32-bit string size, then casts it to a signed integer during a position bounds check without first limiting it to the input buffer. A client application must connect to the crafted server; the resulting overflow can corrupt the client process, causing a crash or arbitrary code execution.

The record

CVE
CVE-2026-53689
Published
Jun 10, 2026
Updated
Jun 10, 2026
Vendor
Ronnie Sahlberg
Product
libnfs
Classifications
CWE-1284, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 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?

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  1. Affected versionversion=0 <55c18ea33a83d667f79f0ef209c96895795c729f

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ronnie Sahlberg · libnfsversion=0 <55c18ea33a83d667f79f0ef209c96895795c729f

Published CVSS scores

7.1MITRECVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L

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-1284Improper Validation of Specified Quantity in Input
T1203Exploitation for Client Execution

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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