SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityReceived

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.

HIGH 7.1EPSS 0.22%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.22%). 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
0.22% probability · 13th percentile
CISA KEV
Not listed
Weakness
CWE-639
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.