CVE-2026-49139CWE-918

Nanobot < 0.2.1 SSRF via Microsoft Teams Channel serviceUrl Poisoning

High · published June 1, 2026

CVSS v4.0
7.0
EPSS
1%
Percentile
51.1
In the wild
Unconfirmed
What it is

Nanobot prior to version 0.2.1 contains a server-side request forgery vulnerability in the Microsoft Teams channel handler that allows remote attackers to exfiltrate Bot Framework bearer tokens by supplying a forged activity with an attacker-controlled serviceUrl value. Attackers can poison the stored conversation reference by sending a crafted inbound activity to the Teams webhook, causing subsequent bot replies to transmit token-bearing Authorization header requests to an attacker-controlled host.

The record
Technical detail
CVSS v4.0
7.0 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:N
EPSS
0.00664 · 51.1th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-06-01T19:50Z
EPSS history
Timeline
  • 01 JUN 19:50Z
    Nanobot < 0.2.1 SSRF via Microsoft Teams Channel serviceUrl Poisoning
    cvelistv5