# CVE-2021-27277: Deserialization in Orion Virtual Infrastructure Monitor

> Local attackers can escalate privileges to SYSTEM via unsafe deserialization in the OneTimeJobSchedulerEventsService WCF service.

- **Severity:** High 7.8 (`CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 22 Apr 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-jv8c-r873-24qg

## What is CVE-2021-27277?

CVE-2021-27277 is a high-severity unsafe deserialization vulnerability in SolarWinds Orion Virtual Infrastructure Monitor, published on 22 Apr 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

This vulnerability allows local attackers to escalate privileges on affected installations of SolarWinds Orion Virtual Infrastructure Monitor 2020.2. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the OneTimeJobSchedulerEventsService WCF service. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-11955.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2021-27277?

It affects 1 product.


Products: Solarwinds Orion Platform.

## How do I fix CVE-2021-27277?

No fix has been published for CVE-2021-27277 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-27277 being exploited?

There is no known exploitation of CVE-2021-27277 in the wild and no public exploit code.

## Other vulnerabilities in SolarWinds Orion Virtual Infrastructure Monitor

- [CVE-2020-10148](https://insights.sbomify.com/CVE-2020-10148/): SolarWinds Orion Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2021-27258](https://insights.sbomify.com/CVE-2021-27258/): Privilege escalation in Orion Platform (critical 9.8)
- [CVE-2021-25274](https://insights.sbomify.com/CVE-2021-25274/): Deserialization in n/a (critical 9.8)
- [CVE-2019-9546](https://insights.sbomify.com/CVE-2019-9546/): Privilege escalation in n/a (critical 9.8)
- [CVE-2020-13169](https://insights.sbomify.com/CVE-2020-13169/): Cross-site scripting in n/a (critical 9.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-27277 and fix it if it is affected.

What it is: CVE-2021-27277 is a high-severity unsafe deserialization vulnerability in SolarWinds Orion Virtual Infrastructure Monitor, published on 22 Apr 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-2021-27277 in the wild and no public exploit code.

Affected product: SolarWinds Orion Virtual Infrastructure Monitor. 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-2021-27277/ (Markdown: https://insights.sbomify.com/CVE-2021-27277/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-27277
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-27277
- OSV: https://osv.dev/vulnerability/CVE-2021-27277

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-27277/
Summaries are generated and may contain mistakes; the official description above is the record.