Stack-based Buffer Overflow in Modem

published 2026-10-12 28 d ago modified 2026-10-16 23 d ago also EUVD-2026-97142

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

In the modem OTA stack, there is a possible stack-based buffer overflow due to improper validation of scheduling information in SIB1 messages. This could lead to remote code execution or denial of service with no additional execution privileges needed.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 24 d ago (2026-10-15)

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Unisoc (Shanghai) Technologies Co., Ltd. Modem

Classification

Weakness

CWE-121 Stack-based Buffer Overflow

References

unisoc.com /en/support/product-security-bulletin/2109454821805424641

Sources

CVE List CVE-2026-66086
NVD CVE-2026-66086

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary