# CVE-2021-25329: Incomplete fix for CVE-2020-9484 > Incomplete fix for CVE-2020-9484 allows remote code execution via deserialization in Apache Tomcat under specific configuration edge cases. - **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/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:** Yes - **Published:** 1 Mar 2021 - **Updated:** 8 Oct 2026 - **Also known as:** BIT-tomcat-2021-25329, CLSA-2024-1716916085, CLSA-2024-1723060627, DEBIAN-CVE-2021-25329, GHSA-jgwr-3qm3-26f3, SUSE-SU-2021:1431-1, UBUNTU-CVE-2021-25329 ## What is CVE-2021-25329? CVE-2021-25329 is a high-severity unsafe deserialization vulnerability in Apache Tomcat, published on 1 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description The fix for CVE-2020-9484 was incomplete. When using Apache Tomcat 10.0.0-M1 to 10.0.0, 9.0.0.M1 to 9.0.41, 8.5.0 to 8.5.61 or 7.0.0. to 7.0.107 with a configuration edge case that was highly unlikely to be used, the Tomcat instance was still vulnerable to CVE-2020-9494. Note that both the previously published prerequisites for CVE-2020-9484 and the previously published mitigations for CVE-2020-9484 also apply to this issue. ## Which versions are affected by CVE-2021-25329? 9 open source packages ship an affected version, including org.apache.tomcat.embed:tomcat-embed-core and tomcat. It affects 12 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 10.0.0-M1 | 10.0.2 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 10.0.0-M1 | 10.0.2 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 7.0.0 | 7.0.108 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 7.0.0 | 7.0.108 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 8.0.0 | 8.5.61 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 8.0.0 | 8.5.61 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 9.0.0 | 9.0.41 | | `org.apache.tomcat.embed:tomcat-embed-core` | Maven | From 9.0.0 | 9.0.41 | | `tomcat` | Bitnami | From 7.0.0 | 7.0.108, 8.5.62, 9.0.42, 10.0.1 | | `tomcat` | SUSE:HPE Helion OpenStack 8 | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:Linux Enterprise Server 12 SP3-BCL | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:OpenStack Cloud 8 | All versions | 8.0.53-29.46.1 | | `tomcat` | SUSE:OpenStack Cloud Crowbar 8 | All versions | 8.0.53-29.46.1 | Products: Apache Tomcat, Debian Debian Linux, Oracle Agile Product Lifecycle Management, Oracle Communications Cloud Native Core Policy, Oracle Communications Cloud Native Core Security Edge Protection Proxy, Oracle Communications Instant Messaging Server, Oracle Database, Oracle Graph Server and Client, Oracle Instantis Enterprisetrack, Oracle Managed File Transfer, Oracle Mysql Enterprise Monitor, Oracle Siebel Ui Framework. ## How do I fix CVE-2021-25329? Upgrade org.apache.tomcat.embed:tomcat-embed-core to a fixed version for your release line: 10.0.2, 7.0.108, 8.5.61 or 9.0.41. ## Is CVE-2021-25329 being exploited? There is no known exploitation of CVE-2021-25329 in the wild and no public exploit code. ## Other vulnerabilities in Apache Tomcat - [CVE-2025-24813](https://insights.sbomify.com/CVE-2025-24813/): Apache Tomcat Path Equivalence (critical 10.0, exploited in the wild) - [CVE-2016-8735](https://insights.sbomify.com/CVE-2016-8735/): Apache Tomcat Remote Code Execution (critical 9.8, exploited in the wild) - [CVE-2017-12617](https://insights.sbomify.com/CVE-2017-12617/): Apache Tomcat Remote Code Execution (high 8.1, exploited in the wild) - [CVE-2017-12615](https://insights.sbomify.com/CVE-2017-12615/): Apache Tomcat on Windows Remote Code Execution (high 8.1, exploited in the wild) - [CVE-2026-34486](https://insights.sbomify.com/CVE-2026-34486/): Apache Tomcat Missing Encryption of Sensitive Data (high 7.5, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2021-25329 and fix it if it is affected. What it is: CVE-2021-25329 is a high-severity unsafe deserialization vulnerability in Apache Tomcat, published on 1 Mar 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-2021-25329 in the wild and no public exploit code. Affected packages and fixed versions: - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 10.0.0-M1; fixed in 10.0.2 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 10.0.0-M1; fixed in 10.0.2 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 7.0.0; fixed in 7.0.108 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 7.0.0; fixed in 7.0.108 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 8.0.0; fixed in 8.5.61 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 8.0.0; fixed in 8.5.61 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 9.0.0; fixed in 9.0.41 - org.apache.tomcat.embed:tomcat-embed-core (Maven): affected from 9.0.0; fixed in 9.0.41 - tomcat (Bitnami): affected from 7.0.0; fixed in 7.0.108, 8.5.62, 9.0.42, 10.0.1 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-2021-25329/ (Markdown: https://insights.sbomify.com/CVE-2021-25329/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-25329 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-25329 - OSV: https://osv.dev/vulnerability/CVE-2021-25329 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-25329/ Summaries are generated and may contain mistakes; the official description above is the record.