# CVE-2020-35491: Serialization gadgets exploit in jackson-databind

> Attackers can execute arbitrary code via deserialization gadgets in jackson-databind when polymorphic typing is enabled.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Dec 2020
- **Updated:** 8 Oct 2026
- **Also known as:** CLEANSTART-2026-CP80171, DEBIAN-CVE-2020-35491, GHSA-r3gr-cxrf-hg25, ROOT-APP-MAVEN-CVE-2020-35491, UBUNTU-CVE-2020-35491

## What is CVE-2020-35491?

CVE-2020-35491 is a high-severity unsafe deserialization vulnerability in Debian Debian Linux, published on 17 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

FasterXML jackson-databind 2.x before 2.9.10.8 mishandles the interaction between serialization gadgets and typing, related to org.apache.commons.dbcp2.datasources.SharedPoolDataSource.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2020-35491?

2 open source packages ship an affected version, including com.fasterxml.jackson.core:jackson-databind. It affects 26 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `com.fasterxml.jackson.core:jackson-databind` | Maven | From 2.0.0 | 2.9.10.8 |
| `com.fasterxml.jackson.core:jackson-databind` | Maven | From 2.0.0 | 2.9.10.8 |

Products: Debian Debian Linux, Fasterxml Jackson-Databind, Netapp Service Level Manager, Oracle Agile Product Lifecycle Management, Oracle Application Testing Suite, Oracle Autovue for Agile Product Lifecycle Management, Oracle Banking Platform, Oracle Banking Treasury Management, Oracle Banking Virtual Account Management, Oracle Blockchain Platform, Oracle Communications Cloud Native Core Policy, Oracle Communications Cloud Native Core Unified Data Repository, Oracle Communications Diameter Signaling Route, Oracle Communications Evolved Communications Application Server, Oracle Communications Instant Messaging Server, Oracle Communications Offline Mediation Controller, Oracle Communications Pricing Design Center, Oracle Communications Services Gatekeeper, Oracle Communications Unified Inventory Management, Oracle Documaker and 6 more.

## How do I fix CVE-2020-35491?

Upgrade com.fasterxml.jackson.core:jackson-databind to 2.9.10.8 or later.

## Is CVE-2020-35491 being exploited?

There is no known exploitation of CVE-2020-35491 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-35491 and fix it if it is affected.

What it is: CVE-2020-35491 is a high-severity unsafe deserialization vulnerability in Debian Debian Linux, published on 17 Dec 2020. 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-2020-35491 in the wild and no public exploit code.

Affected packages and fixed versions:
- com.fasterxml.jackson.core:jackson-databind (Maven): affected from 2.0.0; fixed in 2.9.10.8
- com.fasterxml.jackson.core:jackson-databind (Maven): affected from 2.0.0; fixed in 2.9.10.8

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-2020-35491/ (Markdown: https://insights.sbomify.com/CVE-2020-35491/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-35491
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-35491
- OSV: https://osv.dev/vulnerability/CVE-2020-35491

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-35491/
Summaries are generated and may contain mistakes; the official description above is the record.