CVE-2026-31890
MediumInspektor Gadget is a set of tools and framework for data collection and system inspection on Kubernetes clusters and Linux hosts using eBPF. Prior to 0.50.1, in a situation where the ring-buffer of a gadget is – incidentally or maliciously – already full, the gadget will silently drop events. The include/gadget/buffer.h file contains definitions for the Buffer API that gadgets can use to, among the other things, transfer data from eBPF programs to userspace. For hosts running a modern enough Linux kernel (>= 5.8), this transfer mechanism is based on ring-buffers. The size of the ring-buffer for the gadgets is hard-coded to 256KB. When a gadget_reserve_buf fails because of insufficient space, the gadget silently cleans up without producing an alert. The lost count reported by the eBPF operator, when using ring-buffers – the modern choice – is hardcoded to zero. The vulnerability can be used by a malicious event source (e.g. a compromised container) to cause a Denial Of Service, forcing the system to drop events coming from other containers (or the same container). This vulnerability is fixed in 0.50.1.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-223CVE-2026-31890 is classified as CWE-223
See CWE-223 on MITRE CWE for full details on this weakness type.
References
The following references provide additional information about CVE-2026-31890 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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Exploit Vendor Advisory
Frequently asked questions
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What is CVE-2026-31890?
CVE-2026-31890 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . CVE-2026-31890 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-31890?
CVE-2026-31890 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-31890?
No patch is currently available for CVE-2026-31890. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
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Is CVE-2026-31890 actively exploited?
No — CVE-2026-31890 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.