9.8

CVE-2026-66086: Stack-based Buffer Overflow in Modem

Awaiting analysis
Published 12-10-2026Last modified 15-10-2026

Vulnerability summary

CVE-2026-66086 is a critical (CVSS 9.8) Stack-based Buffer Overflow vulnerability in unisoc (shanghai) technologies co., ltd. modem. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.5% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (NVD)
EPSS score
0.46%
0%100%
Low · Change unavailable
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 12-10-2026
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.46%

Chance of exploitation in the next 30 days

Percentile

39%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

12-10-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Unisoc (shanghai) technologies co., ltd.1 product
  • modemT8100 | T9100 | UDX710

1 vendor · 1 product

References

1 links