How severe is CVE-2025-21735?

CVE-2025-21735 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-21735 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21735?

CVE-2025-21735 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-21735?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-21735 have an EU (EUVD) identifier?

Yes. CVE-2025-21735 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5189.

When was CVE-2025-21735 published?

CVE-2025-21735 was published on 2025-02-27 and last updated on 2026-06-17.

CVE-2025-21735

CVE-2025-21735 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-5189
Weakness: CWE-787
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: NFC: nci: Add bounds checking in nci_hci_create_pipe() The "pipe" variable is a u8 which comes from the network. If it's more than 127, then it results in memory corruption in the caller, nci_hci_connect_gate().

Frequently asked questions

What is CVE-2025-21735?: In the Linux kernel, the following vulnerability has been resolved: NFC: nci: Add bounds checking in nci_hci_create_pipe() The "pipe" variable is a u8 which comes from the network. If it's more than 127, then it results in memory corruption in the caller, nci_hci_connect_gate().
How severe is CVE-2025-21735?: CVE-2025-21735 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-21735 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21735?: CVE-2025-21735 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-21735?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-21735 have an EU (EUVD) identifier?: Yes. CVE-2025-21735 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5189.
When was CVE-2025-21735 published?: CVE-2025-21735 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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