Out-of-bounds write via wrapped name length
Published Apr 27, 2021 · Updated Aug 5, 2024
An integer overflow in NLnet Labs Unbound before 1.9.5 allows attackers to cause an out-of-bounds write during name conversion. The sldns_str2wire_dname_buf_origin function adds relative-name and origin lengths without preventing size_t wraparound, allowing bounds checks to pass before memmove writes beyond the buffer. NLnet Labs disputes the security impact because no path in a running Unbound installation supplies enough controllable input to trigger the overflow remotely or locally.
Summary
What happened
An integer overflow in NLnet Labs Unbound before 1.9.5 allows attackers to cause an out-of-bounds write during name conversion. The sldns_str2wire_dname_buf_origin function adds relative-name and origin lengths without preventing size_t wraparound, allowing bounds checks to pass before memmove writes beyond the buffer. NLnet Labs disputes the security impact because no path in a running Unbound installation supplies enough controllable input to trigger the overflow remotely or locally.
The record
- CVE
- CVE-2019-25034
- Published
- Apr 27, 2021
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, CWE-190
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Apr 27, 2021CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
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Public exploit references
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Technologies
Your stack
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