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CVE-2026-66086

Stack-based Buffer Overflow in Modem

CVSS score

8.3

EPSS probability

—

Risk score

0.8

Published

4 h ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

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Vulnerability description

CVE AI research

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DayBreach AI Explanation

Verified against sources

CVE-2026-66086: Stack-Based Buffer Overflow in Modem OTA Stack

Sources read

1

Source agreement

Tam uyum

Evidence confidence

%53

Short explanation

CVE-2026-66086 is a critical vulnerability in the modem OTA stack caused by improper validation of scheduling information in SIB1 messages, which can lead to a stack-based buffer overflow [S0]. It can result in remote code execution or denial of service without requiring any additional execution privileges [S0].

Why does it matter?

This critical vulnerability poses severe risks to systems due to its potential to enable remote code execution without requiring any prior privileges [S0].

What should be done?

  • Following official vendor security bulletins
  • Applying available patches
  • Monitoring vendor recommendations
Note on uncertainty

The sources give limited detail on some technical conditions. Review the chain of evidence below before deciding how to act.

Chain of evidence and sources2 verified claims

Modem OTA yığınındaki SIB1 mesajlarında zamanlama bilgilerinin uygun olmayan doğrulanması stack tabanlı tampon taşmasına yol açabilir [S0].

S0 · daybreach-canonicalS1 · nvd

Bu zafiyet ek yürütme ayrıcalığına gerek duymadan uzaktan kod yürütme veya hizmet dışı bırakma ile sonuçlanabilir [S0].

S0 · daybreach-canonicalS1 · nvd
Show the technical text from the sources

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

CWE: CWE-121

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-66086 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1Unisoc (Shanghai) Technologies Co., Ltd.Modem View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
9.8CVSS V31CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD
8.3CVSS V3_1HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-66086 is associated with the following CWEs:

CWE-121: Common Weakness Enumeration Entry CWE-121

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-66086 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

https://www.unisoc.com/en/support/product-security-bulletin/2109454821805424641vendor-advisory

CVSS Vector Radar Chart

8.3 / 10
Attack VectorNetworkComplexityLowPrivilegesNoneUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

U(
Unisoc (Shanghai) Technologies Co., Ltd. logo
Unisoc (Shanghai) Technologies Co., Ltd.

Weakness Type (CWE & CAPEC)

CWE-121

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