CVE-2026-82271
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 7.1 HIGHCVSS:4.0/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/M
- EPSS
- 0.39% probability · 33th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-639
- Source
- disclosure@vulncheck.com
EPSS 0.4% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/SciPhi-AI/R2R
- https://github.com/SciPhi-AI/R2R/blob/9c5a94d151f90876bd7eb860f300a8fd662dc481/py/core/main/api/v3/conversations_router.py
- https://github.com/SciPhi-AI/R2R/issues/2292
- https://www.vulncheck.com/advisories/r2r-missing-ownership-check-allows-modifying-other-users-conversations
- https://github.com/SciPhi-AI/R2R/issues/2292
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.