Unknown

CVE-2026-97993 — vhost-vdpa: don't install the eventfd_ctx_fdget() error in config_ctx

In the Linux kernel, the following vulnerability has been resolved: vhost-vdpa: don't install the eventfd_ctx_fdget() error in config_ctx vhost_vdpa_set_config_call() swaps the eventfd_ctx_fdget() return value into v->config_ctx before checking it, so on failure the field briefly holds an ERR_PTR: ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd); swap(ctx, v->config_ctx); if (!IS_ERR_OR_NULL(ctx)) eventfd_ctx_put(ctx); if (IS_ERR(v->config_ctx)) { long ret = PTR_ERR(v->config_ctx); v->config_ctx = NULL; return ret; } Commit 0bde59c1723a ("vhost-vdpa: set v->config_ctx to NULL if eventfd_ctx_fdget() fails") added that clearing, and spelled out the invariant the rest of the file relies on: "we consider 'v->config_ctx' valid if it is not NULL". The window between the swap and the clearing still breaks it. vhost_vdpa_config_cb() only tests for NULL, so a config interrupt delivered inside the window hands the ERR_PTR to eventfd_signal(). Check the fd before installing it instead. That closes the window and matches how vhost_vring_ioctl() handles the same failure for the vq call fd. It also stops a rejected fd from tearing down a config interrupt that was working: until now the swap replaced the live context and put it, so after an EBADF the device silently stopped delivering config interrupts until userspace installed a new fd.

Published Sep 25, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.21%

ahead of 11% of scored CVEs · Oct 15, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < e260dc9fbfdae0978e7a8698f977fbb463a657be≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 66e73fa18910b39fea0941dea5fe091122240855≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 4fde085eb839fbb39c25cbba5d2a091ded394877≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 59fc7c1c6b4d325194ca45352180340092d95098≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 388c678639a0cebfd936b3e56c64ac6a371efec2≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 65faf9eaa00e408e1406fbcf675c8c8d0e27ff2a≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < 6b20b40f020bde236f6b8a08ff88d8653261ec2b≥ 776f395004d829bbbf18c159ed9beb517a208c71 and < e74a9fa50749b9940b4fb13199652325e08d3c4a and 1 more version 5.8	Vulnerable	CVE Program (cve.org) e CISA ADP

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 25, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/e74a9fa50749b9940b4fb13199652325e08d3c4a
NIST National Vulnerability Database
git.kernel.org/stable/c/4fde085eb839fbb39c25cbba5d2a091ded394877
NIST National Vulnerability Database
git.kernel.org/stable/c/e260dc9fbfdae0978e7a8698f977fbb463a657be
NIST National Vulnerability Database
git.kernel.org/stable/c/65faf9eaa00e408e1406fbcf675c8c8d0e27ff2a
NIST National Vulnerability Database
git.kernel.org/stable/c/6b20b40f020bde236f6b8a08ff88d8653261ec2b
NIST National Vulnerability Database
git.kernel.org/stable/c/59fc7c1c6b4d325194ca45352180340092d95098
NIST National Vulnerability Database
git.kernel.org/stable/c/66e73fa18910b39fea0941dea5fe091122240855
NIST National Vulnerability Database
git.kernel.org/stable/c/388c678639a0cebfd936b3e56c64ac6a371efec2
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 1d
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 2d
Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 2d
Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 2d
Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-97993 is "vhost-vdpa: don't install the eventfd_ctx_fdget() error in config_ctx", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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