How severe is CVE-2026-45812?

CVE-2026-45812 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-45812 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45812?

CVE-2026-45812 affects Apache Nimble. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45812?

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

When was CVE-2026-45812 published?

CVE-2026-45812 was published on 2026-07-24 and last updated on 2026-07-27.

CVE-2026-45812

CVE-2026-45812 is a medium-severity vulnerability in Apache Nimble with a CVSS 3.x base score of 6.5. 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-131.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-131
Affected product: Apache Nimble
Published: 2026-07-24
Last modified: 2026-07-27

Description

Incorrect Calculation of Buffer Size vulnerability in Apache NimBLE when processing Legacy Advertising Report HCI event. When a single HCI advertising report event bundles multiple reports, NimBLE miscalculated the offset to the next report. This can cause the host to read past the end of the buffer and deliver a GAP event with bogus data to the application. Severity is low: NimBLE's own controller never batches multiple reports into one event, so this only matters when NimBLE's host is paired with a third-party controller that does. This issue affects Apache NimBLE: through 1.9.0. Users are recommended to upgrade to version 1.10.0, which fixes the issue.

Frequently asked questions

What is CVE-2026-45812?: Incorrect Calculation of Buffer Size vulnerability in Apache NimBLE when processing Legacy Advertising Report HCI event. When a single HCI advertising report event bundles multiple reports, NimBLE miscalculated the offset to the next report. This can cause the host to read past the end of the buffer and deliver a GAP event with bogus data to the application. Severity is low: NimBLE's own controller never batches multiple reports into one event, so this only matters when NimBLE's host is paired with a third-party controller that does. This issue affects Apache NimBLE: through 1.9.0. Users are recommended to upgrade to version 1.10.0, which fixes the issue.
How severe is CVE-2026-45812?: CVE-2026-45812 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-45812 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45812?: CVE-2026-45812 affects Apache Nimble. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45812?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-45812 published?: CVE-2026-45812 was published on 2026-07-24 and last updated on 2026-07-27.

References

Affected products (1)

cpe:2.3:a:apache:nimble:*:*:*:*:*:*:*:*

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