CVE-2009-3623: n/a vulnerability

CVE-2009-3623: The lookup_cb_cred function in fs/nfsd/nfs4callback.c in the nfsd4 subsystem in the Linux kernel before 2.6...

The lookup_cb_cred function in fs/nfsd/nfs4callback.c in the nfsd4 subsystem in the Linux kernel before 2.6.31.2 attempts to access a credentials cache even when a client specifies the AUTH_NULL authentication flavor, which allows remote attackers to cause a denial of service (NULL pointer dereference and system crash) via an NFSv4 mount request.

UnknownCVSS not scoredNot KEV-listedUpdatedAug 7, 2024, 06:38 UTC (UTC+00:00)

Security readout for executives and security teams

CVE-2009-3623 is a Linux kernel NFSv4 server flaw that can let a remote client crash an affected system. The bug is a NULL pointer dereference triggered when nfsd handles an AUTH_NULL NFSv4 mount request. Business impact is service outage, not documented data theft or code execution in the provided sources. Exposure is most likely on Linux systems running vulnerable pre-2.6.31.2 kernels with the NFSv4 server enabled and reachable by untrusted clients. Systems without nfsd/NFSv4 exposure are unlikely to be affected through this path. Prioritize remediation for any reachable NFSv4 server on legacy Linux kernels. The main risk is operational outage from a kernel crash. If NFSv4 is internal-only and systems are on supported kernels, urgency is lower but still worth closing during normal patch cycles. Mitigation focus: Upgrade to a vendor-supported kernel containing the nfsd4 fix.; For upstream 2.6 kernels, confirm the fix included in Linux 2.6.31.2 or later.; Disable NFSv4/nfsd where the service is not required..

Prepared: Jun 28, 2026, 18:15 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

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Vulnerability profileCVE Program record

Severity: Unknown
CVSS: Not scored
Known Exploited: No
Published: Oct 30, 2009, 20:05 UTC (UTC+00:00)

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

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2Source links

CVSS and timeline data

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Source materials

CVE List V5 sourceCVE List V5
https://bugzilla.redhat.com/show_bug.cgi?id=530269CVE reference · x_refsource_CONFIRM

Affected products

Products and packages named in the record

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Weakness

CWE details

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