CVE-2026-82280 QuivrHQ CVE debrief

Who should care

Defenders who manage Quivr systems should assess exposure and verify the vulnerability, as it could allow attackers to modify system prompts and potentially affect all brain users.

Why it matters

CVE-2026-82280 is a high-severity vulnerability in Quivr that allows authenticated users to modify any prompt by identifier, potentially affecting all brain users. Defenders should prioritize verifying the vulnerability and assessing exposure.

• Authenticated users can modify any prompt by identifier
• Attackers with read-only access to shared brains can read exposed prompt identifiers
• System prompts can be overwritten, affecting all brain users

Technical summary

The vulnerability occurs because Quivr fails to validate ownership in prompt endpoints, allowing authenticated users to modify any prompt by identifier. This could potentially allow attackers with read-only access to shared brains to read exposed prompt identifiers and overwrite system prompts, affecting all brain users. The vulnerability affects Quivr version 0.0.322 and has a CVSS score of 7.1, indicating a high-severity vulnerability. Defenders should prioritize verifying the vulnerability and assessing exposure, as the vulnerability could allow attackers to modify system prompts and potentially affect all brain users.

Defensive priority

Defenders should prioritize verifying the vulnerability and assessing exposure, as the vulnerability could allow attackers to modify system prompts and potentially affect all brain users.

Recommended defensive actions

• Verify the vulnerability and assess exposure
• Check if the system is using Quivr version 0.0.322
• Consider implementing additional security measures to prevent attackers from modifying system prompts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is caused by a lack of ownership validation in prompt endpoints, allowing authenticated users to modify any prompt by identifier. The vulnerability affects Quivr version 0.0.322. This issue may allow attackers with read-only access to shared brains to read exposed prompt identifiers and overwrite system prompts, affecting all brain users. Defenders should verify the vulnerability and assess exposure.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.