How severe is CVE-2025-21808?

CVE-2025-21808 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-21808 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21808?

CVE-2025-21808 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-21808?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-21808 have an EU (EUVD) identifier?

Yes. CVE-2025-21808 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5977.

When was CVE-2025-21808 published?

CVE-2025-21808 was published on 2025-02-27 and last updated on 2026-06-17.

CVE-2025-21808

CVE-2025-21808 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-5977
Affected product: Linux Linux Kernel
Published: 2025-02-27
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: net: xdp: Disallow attaching device-bound programs in generic mode Device-bound programs are used to support RX metadata kfuncs. These kfuncs are driver-specific and rely on the driver context to read the metadata. This means they can't work in generic XDP mode. However, there is no check to disallow such programs from being attached in generic mode, in which case the metadata kfuncs will be called in an invalid context, leading to crashes. Fix this by adding a check to disallow attaching device-bound programs in generic mode.

Frequently asked questions

What is CVE-2025-21808?: In the Linux kernel, the following vulnerability has been resolved: net: xdp: Disallow attaching device-bound programs in generic mode Device-bound programs are used to support RX metadata kfuncs. These kfuncs are driver-specific and rely on the driver context to read the metadata. This means they can't work in generic XDP mode. However, there is no check to disallow such programs from being attached in generic mode, in which case the metadata kfuncs will be called in an invalid context, leading to crashes. Fix this by adding a check to disallow attaching device-bound programs in generic mode.
How severe is CVE-2025-21808?: CVE-2025-21808 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21808 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21808?: CVE-2025-21808 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-21808?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21808 have an EU (EUVD) identifier?: Yes. CVE-2025-21808 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5977.
When was CVE-2025-21808 published?: CVE-2025-21808 was published on 2025-02-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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