CVE-2026-85725
LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.5, verify_password in lightrag/api/passwords.py compares plaintext AUTH_ACCOUNTS password values with Python's == operator. The comparison can return after the first mismatching byte, creating response-time differences based on password length and matching prefixes. A network attacker with sufficiently low-latency access can repeatedly query the /login endpoint and use the timing oracle to recover a plaintext-configured password character by character. Deployments using bcrypt-prefixed password values are not affected by this comparison path. This issue is fixed in version 1.5.5.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 27% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 5.9 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N- Weakness
- CWE-208
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-22
- Last modified
- 2026-09-26
- Sources
- NVD
References
- https://github.com/HKUDS/LightRAG/commit/89849c3ed0e0380345a6b5bade027cfb9a5bf32c
- https://github.com/HKUDS/LightRAG/pull/3423
- https://github.com/HKUDS/LightRAG/releases/tag/v1.5.5
- https://github.com/HKUDS/LightRAG/security/advisories/GHSA-c759-cx9p-mrwq
- https://github.com/HKUDS/LightRAG/security/advisories/GHSA-c759-cx9p-mrwq