Service crash via freed YAML parser state
Published Apr 7, 2025 · Updated Apr 8, 2025
Use-after-free in Fluent Bit 3.7.2 allows local users to crash the service by loading a crafted YAML configuration. During YAML parsing, read_config destroys a parser state, then state_pop_with_cleanup passes its freed list to cfl_list_size, which reads the stale heap object. Exploitation requires local ability to supply and load a Fluent Bit configuration file; the demonstrated consequence is a process abort and service interruption.
Summary
What happened
Use-after-free in Fluent Bit 3.7.2 allows local users to crash the service by loading a crafted YAML configuration. During YAML parsing, read_config destroys a parser state, then state_pop_with_cleanup passes its freed list to cfl_list_size, which reads the stale heap object. Exploitation requires local ability to supply and load a Fluent Bit configuration file; the demonstrated consequence is a process abort and service interruption.
The record
- CVE
- CVE-2025-29478
- Published
- Apr 7, 2025
- Updated
- Apr 8, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-400, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 7, 2025CVE publishedPublication date reported by the CVE source.
- Apr 8, 2025Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Fluent Bit YAML configuration use-after-free proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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