Skip to content
Noroxi
CVE-2025-68366· NVD / CVE Program· CNA Linux

nbd: defer config unlock in nbd_genl_connect

In the Linux kernel, the following vulnerability has been resolved: nbd: defer config unlock in nbd_genl_connect There is one use-after-free warning when running NBD_CMD_CONNECT and NBD_CLEAR_SOCK: nbd_genl_connect nbd_alloc_and_init_config // config_refs=1 nbd_start_device // config_refs=2 set NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3 recv_work done // config_refs=2 NBD_CLEAR_SOCK // config_refs=1 close nbd // config_refs=0 refcount_inc -> uaf ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25 refcount_warn_saturate+0x12e/0x290 nbd_genl_connect+0x16d0/0x1ab0 genl_family_rcv_msg_doit+0x1f3/0x310 genl_rcv_msg+0x44a/0x790 The issue can be easily reproduced by adding a small delay before refcount_inc(&nbd->config_refs) in nbd_genl_connect(): mutex_unlock(&nbd->config_lock); if (!ret) { set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags); + printk("before sleep\n"); + mdelay(5 * 1000); + printk("after sleep\n"); refcount_inc(&nbd->config_refs); nbd_connect_reply(info, nbd->index); }

—No exploit Fix available
Published
Dec 24, 2025
Updated
Jun 17, 2026
EPSS
0.2% · 9th percentile
CWE
—
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

Report tools

JSON

Action score

0

Monitor

Low priority for now.

CVSS
0 / 40 · —
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Affected systems

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 4.12affected
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before 330d688a5ca53857828081a3cf31b92ad1b0b3edaffected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before cd93db1b1b4460e6ee77564024ea461e5940f69caffected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before ae3e7bc1f4b393ae20e5c85583eb2c6977374716affected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before 2e5e0665a594f076ef2b9439447bae8be293d09daffected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before c9b99c948b4fb014812afe7b5ccf2db121d22e46affected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before 9a38306643874566d20f7aba7dff9e6f657b51a9affected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before c9e805f6a35d1dd189a9345595a5c20e87611942affected · git
    • e46c7287b1c27683a8e30ca825fb98e2b97f1099 and later · before 1649714b930f9ea6233ce0810ba885999da3b5d4affected · git
    • before 4.12not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10kernelbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64kbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debugbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-develbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-devel-matchedbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-modulesbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-debug-modules-extrabefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-develbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-devel-matchedbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-modulesbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-modules-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-64k-modules-extrabefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-abi-stablelistsbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-cross-headersbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debugbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debug-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debug-develbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debug-devel-matchedbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debug-modulesbefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2
AlmaLinux:10kernel-debug-modules-corebefore 6.12.0-211.20.1.el10_26.12.0-211.20.1.el10_2

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
    40Plan
  • CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
    40Plan
  • CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
    40Plan
  • CVE-2026-74309vdpa/octeon_ep: fix IRQ-to-ring mapping in interrupt handler
    40Plan
  • CVE-2026-74280crypto: marvell/octeontx - fix DMA cleanup using wrong loop index
    40Plan
  • CVE-2026-74279crypto: cavium/cpt - fix DMA cleanup using wrong loop index
    40Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux1649714b930f9ea6233ce0810ba885999da3b5d4Vendor (CNA)
Linux Linux2e5e0665a594f076ef2b9439447bae8be293d09dVendor (CNA)
Linux Linux330d688a5ca53857828081a3cf31b92ad1b0b3edVendor (CNA)
Linux Linux9a38306643874566d20f7aba7dff9e6f657b51a9Vendor (CNA)
Linux Linuxae3e7bc1f4b393ae20e5c85583eb2c6977374716Vendor (CNA)
Linux Linuxc9b99c948b4fb014812afe7b5ccf2db121d22e46Vendor (CNA)
Linux Linuxc9e805f6a35d1dd189a9345595a5c20e87611942Vendor (CNA)
Linux Linuxcd93db1b1b4460e6ee77564024ea461e5940f69cVendor (CNA)
almalinux:kernel5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-core5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-core5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-devel-matched5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules-core5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-debug-modules-extra5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
almalinux:kernel-64k-devel-matched5.14.0-687.12.1.el9_8 · AlmaLinux:9Package registry (OSV)
debian:linux6.1.162-1 · Debian:12Package registry (OSV)
red hat:bpftool-debuginfo0:7.3.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-427.127.1.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)

+5

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

No CVSS vector for this record, so attack conditions can't be derived.

Weakness class (CWE)

—

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records