CVE-2026-57918Network attack vector

RPC state corruption via unchecked PDU subtraction

Published Jun 26, 2026 · Updated Jun 26, 2026

Integer underflow in libnfs through 6.0.2 before 935b8db allows remote attackers controlling an NFS server to corrupt RPC length accounting. READ_IOVEC in rpc_read_from_socket subtracts the expected PDU size from rm_xid[0] without first ensuring that the record-marker value is large enough, causing unsigned wraparound. The client must initiate a connection and process a read reply from a crafted NFS server; the library is not independently exposed as a listening service.

CVSS severity7.1
High
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer underflow in libnfs through 6.0.2 before 935b8db allows remote attackers controlling an NFS server to corrupt RPC length accounting. READ_IOVEC in rpc_read_from_socket subtracts the expected PDU size from rm_xid[0] without first ensuring that the record-marker value is large enough, causing unsigned wraparound. The client must initiate a connection and process a read reply from a crafted NFS server; the library is not independently exposed as a listening service.

The record

CVE
CVE-2026-57918
Published
Jun 26, 2026
Updated
Jun 26, 2026
Vendor
Ronnie Sahlberg
Product
libnfs
Classifications
CWE-191
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 26, 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=0 <935b8db712b3c6649bc57ddc276526c4a31680de

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ronnie Sahlberg · libnfsversion=0 <935b8db712b3c6649bc57ddc276526c4a31680de

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-191Integer Underflow (Wrap or Wraparound)

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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