7.1
HIGH CVSS 4.0
CVE-2026-82271
R2R Missing Ownership Check Allows Modifying Other Users' Conversations
Description

R2R through 3.6.5 fails to properly validate user ownership in conversation update and message handlers, allowing authenticated users to modify other users' conversations. Attackers can supply arbitrary conversation identifiers to rename conversations and append messages to other users' conversation histories, corrupting state and injecting malicious content.

INFO

Published Date :

Aug. 28, 2026, 8:20 p.m.

Last Modified :

Aug. 28, 2026, 8:20 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-82271 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Properly validate user ownership in conversation and message handlers to prevent unauthorized modifications.
  • Implement strict user ownership validation for all conversation operations.
  • Ensure all message handler inputs are validated against ownership.
  • Review and update conversation and message handling logic.
  • Apply updates for R2R versions 3.6.5 and earlier.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-82271 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-82271 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-82271 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-82271 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Description R2R through 3.6.5 fails to properly validate user ownership in conversation update and message handlers, allowing authenticated users to modify other users' conversations. Attackers can supply arbitrary conversation identifiers to rename conversations and append messages to other users' conversation histories, corrupting state and injecting malicious content.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
    Added CWE CWE-639
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/82xxx/CVE-2026-82271.json">CVE-2026-82271</a>
    Added Reference https://github.com/SciPhi-AI/R2R
    Added Reference https://github.com/SciPhi-AI/R2R/blob/9c5a94d151f90876bd7eb860f300a8fd662dc481/py/core/main/api/v3/conversations_router.py
    Added Reference https://github.com/SciPhi-AI/R2R/issues/2292
    Added Reference https://www.vulncheck.com/advisories/r2r-missing-ownership-check-allows-modifying-other-users-conversations
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.