CVE-2026-57918: CWE-191 Integer Underflow (Wrap or Wraparound) in sahlberg libnfs
libnfs through 6.0.2 before 935b8db has an xid integer underflow in READ_IOVEC in rpc_read_from_socket in lib/socket.c during a connection to a crafted NFS server, when the expected pdu size exceeds the absolute pdu size from the xid/record-marker.
AI Analysis
Technical Summary
The vulnerability CVE-2026-57918 in libnfs (up to version 6.0.2 before commit f0b109d) is an integer underflow (CWE-191) in the READ_IOVEC function of rpc_read_from_socket (lib/socket.c). It is triggered during a connection to a maliciously crafted NFS server when the expected PDU size is larger than the absolute PDU size indicated by the xid/record-marker, leading to an integer underflow condition. This can potentially impact confidentiality, integrity, and availability with high severity as per the CVSS 3.1 vector AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L.
Potential Impact
Successful exploitation of this integer underflow could lead to high impact on confidentiality and integrity, and a low impact on availability. The vulnerability could allow an attacker controlling an NFS server to cause unexpected behavior in the client, potentially leading to data compromise or corruption. However, exploitation requires user interaction (UI:R) and high attack complexity (AC:H).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are currently available. Users should monitor the vendor's announcements for updates and apply any forthcoming patches promptly. Until a fix is available, avoid connecting to untrusted or malicious NFS servers to reduce risk.
CVE-2026-57918: CWE-191 Integer Underflow (Wrap or Wraparound) in sahlberg libnfs
Description
libnfs through 6.0.2 before 935b8db has an xid integer underflow in READ_IOVEC in rpc_read_from_socket in lib/socket.c during a connection to a crafted NFS server, when the expected pdu size exceeds the absolute pdu size from the xid/record-marker.
CVSS v3.1
Score 7.1high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-57918 in libnfs (up to version 6.0.2 before commit f0b109d) is an integer underflow (CWE-191) in the READ_IOVEC function of rpc_read_from_socket (lib/socket.c). It is triggered during a connection to a maliciously crafted NFS server when the expected PDU size is larger than the absolute PDU size indicated by the xid/record-marker, leading to an integer underflow condition. This can potentially impact confidentiality, integrity, and availability with high severity as per the CVSS 3.1 vector AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L.
Potential Impact
Successful exploitation of this integer underflow could lead to high impact on confidentiality and integrity, and a low impact on availability. The vulnerability could allow an attacker controlling an NFS server to cause unexpected behavior in the client, potentially leading to data compromise or corruption. However, exploitation requires user interaction (UI:R) and high attack complexity (AC:H).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are currently available. Users should monitor the vendor's announcements for updates and apply any forthcoming patches promptly. Until a fix is available, avoid connecting to untrusted or malicious NFS servers to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-06-26T10:54:57.765Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3e5c034853345fc1b7bab6
Added to database: 06/26/2026, 11:01:23 UTC
Last enriched: 06/26/2026, 11:15:56 UTC
Last updated: 06/26/2026, 12:04:04 UTC
Views: 5
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