Fluent bit: UNKNOWN READ in renumber_by_map
Description
A vulnerability in Fluent Bit causes an UNKNOWN READ crash in the renumber_by_map function. This issue was identified by OSS-Fuzz and affects multiple specific versions of Fluent Bit. A patch is available to address this vulnerability.
Affected software
pkg:generic/fluent-bitRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The OSS-Fuzz project reported a crash in Fluent Bit characterized as an UNKNOWN READ occurring in the renumber_by_map function, specifically during calls to renumber_by_map and disable_noname_group_capture. This indicates a memory access issue that could lead to instability or denial of service in affected versions. The vulnerability affects multiple explicitly listed versions of Fluent Bit, including 4.2.1, 4.2.2, and several 5.x releases up to 5.1.1. A patch is available, though no direct link to the patch was provided in the data.
Potential Impact
The vulnerability causes a crash due to an unknown memory read, which may lead to application instability or denial of service. There is no evidence of known exploits in the wild or further impact such as code execution from the provided data.
Mitigation Recommendations
A patch is available for this vulnerability. Users should apply the official fix from Fluent Bit to the affected versions listed. Since the vendor advisory or patch links were not provided, users should consult the Fluent Bit project or OSS-Fuzz for the latest patched releases and apply updates accordingly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- OSV-2026-1235
- Osv Schema Version
- 1.9.0
- Ecosystems
- ["OSS-Fuzz"]
Threat ID: 6a9d7635acd9273b49d80606
Added to database: 09/06/2026, 14:18:29 UTC
Last enriched: 09/07/2026, 09:37:39 UTC
Last updated: 10/04/2026, 08:48:44 UTC
Views: 123
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