# CVE-2026-49139: Nanobot < 0.2.1 SSRF via Microsoft Teams Channel serviceUrl Poisoning

> Remote attackers can exfiltrate Bot Framework bearer tokens by poisoning Microsoft Teams serviceUrl values, leading to unauthorized data access.

- **Severity:** High 7.0 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Jun 2026
- **Updated:** 28 Jul 2026
- **Also known as:** GHSA-gv7x-pq3j-c5mj

## What is CVE-2026-49139?

CVE-2026-49139 is a high-severity server-side request forgery vulnerability in HKUDS nanobot, published on 1 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-49139?


## How do I fix CVE-2026-49139?

No fix has been published for CVE-2026-49139 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-49139 being exploited?

There is no known exploitation of CVE-2026-49139 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49139 and fix it if it is affected.

What it is: CVE-2026-49139 is a high-severity server-side request forgery vulnerability in HKUDS nanobot, published on 1 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-49139 in the wild and no public exploit code.

Affected product: HKUDS nanobot. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-49139/ (Markdown: https://insights.sbomify.com/CVE-2026-49139/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49139
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49139
- OSV: https://osv.dev/vulnerability/CVE-2026-49139

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-49139/
Summaries are generated and may contain mistakes; the official description above is the record.