Is CVE-2026-26399 in the CISA KEV catalog?

No. CVE-2026-26399 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-26399?

CVE-2026-26399 has a CVSS v3 base score of 5.3 (MEDIUM).

What is the EPSS score for CVE-2026-26399?

CVE-2026-26399 has an EPSS score of 0.18% (8th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix or mitigate CVE-2026-26399?

No published fix for CVE-2026-26399 has been found yet. Check the linked vendor advisories for guidance as it becomes available.

CVE & CISA-KEV Catalog

CVE-2026-26399

MEDIUM

5.3

CVSS v3

NVD

Description

A stack-use-after-return issue exists in the Arduino_Core_STM32 library prior to version 1.7.0. The pwm_start() function allocates a TIM_HandleTypeDef structure on the stack and passes its address to HAL initialization routines, where it is stored in a global timer handle registry. After the function returns, interrupt service routines may dereference this dangling pointer, resulting in memory corruption.

CWE-562

How to fix

No published remediation has been found for this vulnerability's affected products yet.

Mitigation guidance may be in the linked vendor advisories in the References section below.

CVSS v3 Vector

Exploitability

Attack VectorLocal

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityLow

AvailabilityLow

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Exploit Intelligence

0.18%probability of exploitation in 30 days

8thpercentile

Low risk: more likely to be exploited than 8% of all known CVEs.

References

Other references2

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-22.