Memory disclosure or crash via malformed DNS response
Published Apr 22, 2021 · Updated Aug 4, 2024
Out-of-bounds read in Siemens Nucleus RTOS-based products allows context-dependent attackers to leak memory or crash devices. The DNS response parser trusts malformed record lengths and counts, causing it to read beyond an allocated structure. Exploitation requires a privileged network position from which crafted DNS responses can be supplied; the bounded consequences are memory disclosure and service interruption.
Summary
What happened
Out-of-bounds read in Siemens Nucleus RTOS-based products allows context-dependent attackers to leak memory or crash devices. The DNS response parser trusts malformed record lengths and counts, causing it to read beyond an allocated structure. Exploitation requires a privileged network position from which crafted DNS responses can be supplied; the bounded consequences are memory disclosure and service interruption.
The record
- CVE
- CVE-2020-27737
- Published
- Apr 22, 2021
- Updated
- Aug 4, 2024
- Vendor
- Siemens
- Product
- TALON TC Compact (BACnet)
- Classifications
- CWE-125, T1557
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 22, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 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?
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- Affected versionversion=All versions < V3.5.5
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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