What is CVE-2026-20434?

CVE-2026-20434 is a high-severity vulnerability in Mediatek Lr12a, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2026-03-02.

How severe is CVE-2026-20434?

High severity. CVSS v3 base score is 7.5 out of 10.

Buffer overflow in Mediatek Lr12a

CVE-2026-20434

In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution priv…

Vulnerability class: Buffer Overflow

EPSS: 0.002 (12.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Mediatek Lr12a
Mediatek Lr13
Mediatek Mt2735
Mediatek Mt2737
Mediatek Mt6739
Mediatek Mt6761
Mediatek Mt6762
Mediatek Mt6762d
Mediatek Mt6762m
Mediatek Mt6763

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

security@mediatek.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-20434?: CVE-2026-20434 is a high-severity vulnerability in Mediatek Lr12a, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2026-03-02.
How severe is CVE-2026-20434?: High severity. CVSS v3 base score is 7.5 out of 10.