# CVE-2026-85725: LightRAG plaintext password timing attack vulnerability

Source: https://junglewise.ai/threats/cve-2026-85725-lightrag-plaintext-password-timing-attack-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-22. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-85725 · Severity: medium · CVSS 5.9 · Published 2026-09-22

LightRAG is a Python library that provides API authentication. When plaintext passwords are stored (not hashed), the password verification code uses a non-constant-time comparison that leaks password information through timing side-channels. An attacker with network access can measure response times to systematically recover passwords character-by-character without hitting brute-force protections, compromising account security for systems using plaintext password storage.

Technologies: [HKUDS LightRAG](https://junglewise.ai/threats/technologies/lightrag), [lightrag-hku (PyPI)](https://junglewise.ai/threats/technologies/lightrag-hku). Vendors: [HKUDS](https://junglewise.ai/threats/vendors/hkuds), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-85725 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-85725 being exploited in the wild.

**How severe is CVE-2026-85725?** Medium severity, with a CVSS score of 5.9, published 22 September 2026.

**Which products and versions are affected?** HKUDS LightRAG <= 1.5.4; lightrag-hku (PyPI) <= 1.5.4, ECOSYSTEM:introduced=0,fixed=1.5.5.

**Is there a fix for CVE-2026-85725?** Yes. lightrag-hku (PyPI): upgrade to 1.5.5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-85725 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-85725?** Check whether you run HKUDS LightRAG or lightrag-hku (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- lightrag-hku (PyPI): upgrade to 1.5.5 or later

  ```sh
  pip install "lightrag-hku>=1.5.5"
  ```


## Technical details

The vulnerability is a timing oracle in the verify_password() function (lightrag/api/passwords.py:13-26) that compares plaintext passwords using Python's == operator instead of a constant-time comparison function. The == operator short-circuits on the first mismatched byte, causing measurably different response times based on how many characters match. An attacker with low-latency network access can measure login endpoint response times to determine each character of the password sequentially without triggering brute-force detection. The vulnerability only affects deployments where AUTH_ACCOUNTS contains plaintext passwords rather than bcrypt hashes. A proof-of-concept exploit demonstrates character-by-character password recovery via timing measurement. The fix is available in version 1.5.5, which presumably implements constant-time comparison.

## Affected products

- HKUDS LightRAG <= 1.5.4

## Identifiers

- CVE-2026-85725
- GHSA-c759-cx9p-mrwq
- PYSEC-2026-4061

## Timeline

- 2026-07-18: disclosed: Published to GitHub Advisory Database
- 2026-09-22: advisory: Published to NVD
- 2026-09-22: patched: Version 1.5.5 released with fix

## References

- [https://api.github.com/users/MaramHarsha](https://api.github.com/users/MaramHarsha)

## Related threats

- [LightRAG WebUI stored XSS in chat answer renderer](https://junglewise.ai/threats/cve-2026-86062-lightrag-webui-stored-xss-in-chat-answer-renderer)
- [LightRAG SSRF via IPv6-transition address bypass in markdown image download](https://junglewise.ai/threats/cve-2026-85740-lightrag-ssrf-via-ipv6-transition-address-bypass-in-markdown)
- [lightrag-hku /login endpoint missing rate limiting enables brute-force attacks](https://junglewise.ai/threats/cve-2026-85734-lightrag-hku-login-endpoint-missing-rate-limiting-enables-brute)
- [LightRAG API sensitive information exposure in error responses](https://junglewise.ai/threats/cve-2026-85709-lightrag-api-sensitive-information-exposure-in-error-responses)
- [HKUDS LightRAG authentication bypass in API-key-only mode](https://junglewise.ai/threats/cve-2026-61740-hkuds-lightrag-authentication-bypass-in-api-key-only-mode)