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TI-2026-85049 Aliases CVE-2026-121938GHSA-j5gc-wvrm-78hc

Missing ownership check in langchain4j-aideepin exposes chats

Priority MEDIUM 60CWE-639Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-639.

Summary

langchain4j-aideepin before 3.31.0 contains an insecure direct object reference (CWE-639) that lets authenticated users read other users' character chat conversations by supplying their character uuid. CharacterService.detail resolves the character without an ownership check, which exposes victims' questions, AI answers, and attachment and audio URLs.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

langchain4j-aideepin before 3.31.0 contains an insecure direct object reference vulnerability that allows authenticated users to read other users' character-chat conversations by supplying their character uuid. Attackers can request GET /character/{uuid}, which CharacterService.detail resolves without an ownership check, to obtain victims' questions, AI answers, and attachment and audio URLs.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00391 33rd percentileScored 2026-11-07
Fix Fixed langchain4j-aideepin (moyangzhan): 3.31.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
moyangzhanlangchain4j-aideepinbefore 3.31.03.31.0Patch availableCNA
  • langchain4j-aideepin Vendormoyangzhan Affected before 3.31.0 Fixed in 3.31.0 Patch available CNA

Remediation

Upgrade langchain4j-aideepin to 3.31.0, the fixed version.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA langchain4j-aideepin (moyangzhan) Fixed in 3.31.0

Timeline

  1. 2026-11-04 Threatist record created from CVE-2026-121938
  2. 2026-11-04 Alias added: GHSA-j5gc-wvrm-78hc
  3. 2026-11-04 CISA SSVC decision points changed

References

Patch 2

Advisory 1

Other 2

  • TI-2025-15564 LangChain4j-AIDeepin Using MD5 to Hash files may cause file upload conflicts CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences