# CVE-2021-34711: Cisco IP Phone Software Arbitrary File Read Vulnerability

> An authenticated local attacker can read arbitrary files on Cisco IP Phones via insufficient input validation in the debug shell.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Oct 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-rh9c-8fw7-2j3p

## What is CVE-2021-34711?

CVE-2021-34711 is a medium-severity path traversal vulnerability in Cisco IP Phones with Multiplatform Firmware, published on 6 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the debug shell of Cisco IP Phone software could allow an authenticated, local attacker to read any file on the device file system. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by providing crafted input to a debug shell command. A successful exploit could allow the attacker to read any file on the device file system.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), CWE-36 (Absolute Path Traversal)

## Which versions are affected by CVE-2021-34711?

It affects 16 products.


Products: Cisco Ip Conference Phone 7832 Firmware, Cisco Ip Conference Phone 8832 Firmware, Cisco Ip Phone 7811 Firmware, Cisco Ip Phone 7821 Firmware, Cisco Ip Phone 7832 Firmware, Cisco Ip Phone 7841 Firmware, Cisco Ip Phone 7861 Firmware, Cisco Ip Phone 8811 Firmware, Cisco Ip Phone 8831 Firmware, Cisco Ip Phone 8841 Firmware, Cisco Ip Phone 8845 Firmware, Cisco Ip Phone 8851 Firmware, Cisco Ip Phone 8861 Firmware, Cisco Ip Phone 8865 Firmware, Cisco Ip Phones 8832 Firmware, Cisco Wireless Ip Phone 8821 Firmware.

## How do I fix CVE-2021-34711?

No fix has been published for CVE-2021-34711 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34711 being exploited?

There is no known exploitation of CVE-2021-34711 in the wild and no public exploit code.

## Other vulnerabilities in Cisco IP Phones with Multiplatform Firmware

- [CVE-2020-3111](https://insights.sbomify.com/CVE-2020-3111/): Cisco IP Phone Remote Code Execution and Denial of Service Vulnerability (high 8.8)
- [CVE-2019-1635](https://insights.sbomify.com/CVE-2019-1635/): Cisco IP Phone 7800 Series and 8800 Series Session Initiation Protocol XML Denial of Service Vulnerability (high 7.5)
- [CVE-2021-1379](https://insights.sbomify.com/CVE-2021-1379/): Memory corruption in Cisco IP Phones with Multiplatform Firmware (medium 6.5)
- [CVE-2019-1684](https://insights.sbomify.com/CVE-2019-1684/): Denial of service in Cisco IP Phone 8800 Series Software (medium 6.5)
- [CVE-2019-1922](https://insights.sbomify.com/CVE-2019-1922/): Cisco IP Phone 7800 and 8800 Series Session Initiation Protocol Denial of Service Vulnerability (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34711 and fix it if it is affected.

What it is: CVE-2021-34711 is a medium-severity path traversal vulnerability in Cisco IP Phones with Multiplatform Firmware, published on 6 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-34711 in the wild and no public exploit code.

Affected product: Cisco IP Phones with Multiplatform Firmware. 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-2021-34711/ (Markdown: https://insights.sbomify.com/CVE-2021-34711/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34711
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34711
- OSV: https://osv.dev/vulnerability/CVE-2021-34711

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-34711/
Summaries are generated and may contain mistakes; the official description above is the record.