Service interruption via unreleased helper buffers
Published Jan 7, 2020 · Updated Aug 5, 2024
Memory leak in create_helper() in Simon Kelley's dnsmasq before 2.81 allows remote attackers to exhaust memory through crafted DHCP responses. In src/helper.c, alloc_buff was reset to NULL on every loop iteration, so an oversized-data buffer allocated by malloc() was never released before its pointer was lost. The helper path requires a specific domain-name configuration and repeated triggering, eventually terminating the process and interrupting DNS and DHCP service.
Summary
What happened
Memory leak in create_helper() in Simon Kelley's dnsmasq before 2.81 allows remote attackers to exhaust memory through crafted DHCP responses. In src/helper.c, alloc_buff was reset to NULL on every loop iteration, so an oversized-data buffer allocated by malloc() was never released before its pointer was lost. The helper path requires a specific domain-name configuration and repeated triggering, eventually terminating the process and interrupting DNS and DHCP service.
The record
- CVE
- CVE-2019-14834
- Published
- Jan 7, 2020
- Updated
- Aug 5, 2024
- Vendor
- Simon Kelley
- Product
- dnsmasq
- Classifications
- CWE-770, T1499.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 7, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 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=before 2.81
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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