CVE-2026-5759
CVE-2026-5759 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-415.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v4: 9.3
- EPSS exploit prediction: 1% (45th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-415
- Published:
- Last modified:
Description
A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of the RDB graph decoders (src/serializers/decoders/*/decode_graph_entities.c) in FalkorDB before 4.18.1 allows a remote attacker who can issue Redis replication commands (for example, against an instance with no password configured) to cause a denial of service or execute arbitrary code in the redis-server process by supplying a crafted RDB stream whose deleted-nodes buffer length is not a multiple of sizeof(NodeID). The length check relies on ASSERT(), which is compiled out in release builds, so the function continues after freeing the buffer, reading it and freeing it a second time.
Frequently asked questions
- What is CVE-2026-5759?
- A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of the RDB graph decoders (src/serializers/decoders/*/decode_graph_entities.c) in FalkorDB before 4.18.1 allows a remote attacker who can issue Redis replication commands (for example, against an instance with no password configured) to cause a denial of service or execute arbitrary code in the redis-server process by supplying a crafted RDB stream whose deleted-nodes buffer length is not a multiple of sizeof(NodeID). The length check relies on ASSERT(), which is compiled out in release builds, so the function continues after freeing the buffer, reading it and freeing it a second time.
- How severe is CVE-2026-5759?
- CVE-2026-5759 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-5759 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-5759?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2026-5759 published?
- CVE-2026-5759 was published on 2026-10-09 and last updated on 2026-10-13.
References
- https://github.com/FalkorDB/FalkorDB/commit/523d98ac7ffe99f11a9c95c258025c235f0dff4c
- https://github.com/FalkorDB/FalkorDB/pull/1843
- https://github.com/FalkorDB/FalkorDB/releases/tag/v4.18.1
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