CVE-2021-30307Network attack vector

Remote service interruption via malformed DNS response

Published Jan 13, 2022 · Updated Aug 3, 2024

Reachable assertion in Qualcomm Snapdragon data modems allows remote attackers to interrupt service through a crafted DNS response. The modem DNS client inadequately validates a response received after issuing a PTR, NAPTR, or SRV query, allowing malformed response data to reach an assertion. No authentication or user interaction is required; triggering the assertion disrupts availability, while confidentiality and data modification are not reported.

CVSS severity7.5
High
EPSS probability0.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in Qualcomm Snapdragon data modems allows remote attackers to interrupt service through a crafted DNS response. The modem DNS client inadequately validates a response received after issuing a PTR, NAPTR, or SRV query, allowing malformed response data to reach an assertion. No authentication or user interaction is required; triggering the assertion disrupts availability, while confidentiality and data modification are not reported.

The record

CVE
CVE-2021-30307
Published
Jan 13, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-617, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5Qualcomm Technologies, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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