How severe is CVE-2025-7403?

CVE-2025-7403 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2025-7403 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-7403?

CVE-2025-7403 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-7403?

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-2025-7403 have an EU (EUVD) identifier?

Yes. CVE-2025-7403 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30240.

When was CVE-2025-7403 published?

CVE-2025-7403 was published on 2025-09-19 and last updated on 2026-06-17.

CVE-2025-7403

CVE-2025-7403 is a high-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 7.6. 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-123.

Key facts

Severity: High (CVSS 3.x base score 7.6)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-30240
Weakness: CWE-123
Affected product: Zephyrproject Zephyr
Published: 2025-09-19
Last modified: 2026-06-17

Description

Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in a write-before-zero. The written 4 bytes are attacker-controlled, enabling precise memory corruption.

Frequently asked questions

What is CVE-2025-7403?: Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in a write-before-zero. The written 4 bytes are attacker-controlled, enabling precise memory corruption.
How severe is CVE-2025-7403?: CVE-2025-7403 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2025-7403 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-7403?: CVE-2025-7403 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-7403?: 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-2025-7403 have an EU (EUVD) identifier?: Yes. CVE-2025-7403 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30240.
When was CVE-2025-7403 published?: CVE-2025-7403 was published on 2025-09-19 and last updated on 2026-06-17.

References

https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9r46-cqqw-6j2j

Affected products (1)

cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*

More vulnerabilities in Zephyrproject Zephyr

CVE-2026-5067 — Critical (CVSS 9.8): A remote, unauthenticated attacker can trigger memory corruption in Zephyr's HTTP server WebSocket upgrade path by…
CVE-2022-3806 — Critical (CVSS 9.8): Inconsistent handling of error cases in bluetooth hci may lead to a double free condition of a network buffer.
CVE-2017-14199 — Critical (CVSS 9.8): A buffer overflow has been found in the Zephyr Project's getaddrinfo() implementation in 1.9.0 and 1.10.0.
CVE-2018-1000800 — Critical (CVSS 9.8): zephyr-rtos version 1.12.0 contains a NULL base pointer reference vulnerability in sys_ring_buf_put(),…
CVE-2021-3329 — Critical (CVSS 9.6): Lack of proper validation in HCI Host stack initialization can cause a crash of the bluetooth stack
CVE-2023-0397 — Critical (CVSS 9.6): A malicious / defect bluetooth controller can cause a Denial of Service due to unchecked input in…

All CVEs affecting Zephyrproject Zephyr →

Other CWE-123 vulnerabilities

CVE-2025-69809 — Critical (CVSS 9.8): A write-what-where condition in p2r3 Bareiron commit 8e4d40 allows unauthenticated attackers to write arbitrary values…
CVE-2022-38143 — Critical (CVSS 9.8): A heap out-of-bounds write vulnerability exists in the way OpenImageIO v2.3.19.0 processes RLE encoded BMP images. A…
CVE-2021-38449 — Critical (CVSS 9.8): Some API functions permit by-design writing or copying data into a given buffer. Since the client controls these…
CVE-2015-8271 — Critical (CVSS 9.8): The AMF3CD_AddProp function in amf.c in RTMPDump 2.4 allows remote RTMP Media servers to execute arbitrary code.
CVE-2026-30121 — Critical (CVSS 9.1): remotion-dev remotion v4.0.409 was discovered to contain an arbitrary file write vulnerability.
CVE-2026-43284 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: avoid in-place decrypt on shared skb…

Browse all CWE-123 vulnerabilities →