# CVE-2020-13956: Cross-site scripting in Apache HttpClient > Apache HttpClient may route requests to unintended hosts due to malformed URI parsing, enabling potential SSRF or security bypass. - **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 2 Dec 2020 - **Updated:** 8 Oct 2026 - **Also known as:** ALSA-2022:1860, ALSA-2022:1861, CLEANSTART-2025-XW98156, CLSA-2025-1765325275, CLSA-2026-1784682871, CLSA-2026-1785291356, CLSA-2026-1785291357, CLSA-2026-1785291358, CLSA-2026-1786354766, CLSA-2026-1786947088, CLSA-2026-1789379188, CLSA-2026-1789379710, CLSA-2026-1789400657, CLSA-2026-1789471072, CLSA-2026-1789556475, CLSA-2026-1791898812, CLSA-2026-1792744544, CLSA-2026-1792744871, CLSA-2026-1792745336, DEBIAN-CVE-2020-13956, DLA-2405-1, DSA-4772-1, ECHO-0b6b-adeb-84a3, GHSA-7r82-7xv7-xcpj, MGASA-2021-0314, MINI-96gq-v32h-ccjh, RHLW-2026-7b188d550bf6bfc3, RHLW-2026-e6d7b954cd8149d6, RHSA-2022:0722, RHSA-2022:1860, RHSA-2022:1861, RLSA-2022:1860, RLSA-2022:1861, SUSE-SU-2024:4036-1, UBUNTU-CVE-2020-13956, USN-5239-1, openSUSE-SU-2024:14478-1 ## What is CVE-2020-13956? CVE-2020-13956 is a medium-severity server-side request forgery vulnerability in Netapp Active Iq Unified Manager, published on 2 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Apache HttpClient versions prior to version 4.5.13 and 5.0.3 can misinterpret malformed authority component in request URIs passed to the library as java.net.URI object and pick the wrong target host for request execution. Weakness: CWE-20 (Improper Input Validation) ## Which versions are affected by CVE-2020-13956? 4 open source packages ship an affected version, including org.apache.httpcomponents:httpclient. It affects 17 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `org.apache.httpcomponents:httpclient` | Maven | All versions | 4.5.13 | | `org.apache.httpcomponents:httpclient` | Maven | All versions | 4.5.13 | | `org.apache.httpcomponents:httpclient` | Maven | From 5.0.0 | 5.0.3 | | `org.apache.httpcomponents:httpclient` | Maven | From 5.0.0 | 5.0.3 | | `aopalliance` | AlmaLinux:8 | All versions | 1.0-17.module_el8.6.0+2752+f1f3449e | | `aopalliance` | AlmaLinux:8 | All versions | 1.0-20.module_el8.6.0+2786+d7c38b21 | | `apache-commons-cli` | AlmaLinux:8 | All versions | 1.4-4.module_el8.6.0+2752+f1f3449e | | `apache-commons-cli` | AlmaLinux:8 | All versions | 1.4-7.module_el8.6.0+2786+d7c38b21 | | `apache-commons-codec` | AlmaLinux:8 | All versions | 1.11-3.module_el8.6.0+2752+f1f3449e | | `apache-commons-codec` | AlmaLinux:8 | All versions | 1.13-3.module_el8.6.0+2786+d7c38b21 | | `apache-commons-io` | AlmaLinux:8 | All versions | 1:2.6-3.module_el8.6.0+2752+f1f3449e | | `apache-commons-io` | AlmaLinux:8 | All versions | 1:2.6-6.module_el8.6.0+2786+d7c38b21 | | `apache-commons-lang3` | AlmaLinux:8 | All versions | 3.7-3.module_el8.6.0+2752+f1f3449e | | `apache-commons-lang3` | AlmaLinux:8 | All versions | 3.9-4.module_el8.6.0+2786+d7c38b21 | | `apache-commons-logging` | AlmaLinux:8 | All versions | 1.2-13.module_el8.6.0+2752+f1f3449e | | `atinject` | AlmaLinux:8 | All versions | 1-28.20100611svn86.module_el8.6.0+2752+f1f3449e | | `atinject` | AlmaLinux:8 | All versions | 1-31.20100611svn86.module_el8.6.0+2786+d7c38b21 | | `cdi-api` | AlmaLinux:8 | All versions | 1.2-8.module_el8.6.0+2752+f1f3449e | | `cdi-api` | AlmaLinux:8 | All versions | 2.0.1-3.module_el8.6.0+2786+d7c38b21 | | `geronimo-annotation` | AlmaLinux:8 | All versions | 1.0-23.module_el8.6.0+2752+f1f3449e | | `geronimo-annotation` | AlmaLinux:8 | All versions | 1.0-26.module_el8.6.0+2786+d7c38b21 | | `glassfish-el-api` | AlmaLinux:8 | All versions | 3.0.1-0.7.b08.module_el8.6.0+2752+f1f3449e | | `google-guice` | AlmaLinux:8 | All versions | 4.1-11.module_el8.6.0+2752+f1f3449e | | `google-guice` | AlmaLinux:8 | All versions | 4.2.2-4.module_el8.6.0+2786+d7c38b21 | | `guava` | AlmaLinux:8 | All versions | 28.1-3.module_el8.6.0+2786+d7c38b21 | | `guava20` | AlmaLinux:8 | All versions | 20.0-8.module_el8.6.0+2752+f1f3449e | | `hawtjni-runtime` | AlmaLinux:8 | All versions | 1.16-2.module_el8.6.0+2752+f1f3449e | | `httpcomponents-client` | AlmaLinux:8 | All versions | 4.5.10-4.module_el8.6.0+2786+d7c38b21 | | `httpcomponents-client` | AlmaLinux:8 | All versions | 4.5.5-5.module_el8.6.0+2752+f1f3449e | | `httpcomponents-core` | AlmaLinux:8 | All versions | 4.4.10-3.module_el8.6.0+2752+f1f3449e | | `httpcomponents-core` | AlmaLinux:8 | All versions | 4.4.12-3.module_el8.6.0+2786+d7c38b21 | | `jansi` | AlmaLinux:8 | All versions | 1.17.1-1.module_el8.0.0+6044+f3cbc35d | | `jansi` | AlmaLinux:8 | All versions | 1.17.1-1.module_el8.4.0+2250+516cbbff | | `jansi` | AlmaLinux:8 | All versions | 1.17.1-1.module_el8.6.0+2752+f1f3449e | | `jansi` | AlmaLinux:8 | All versions | 1.18-4.module_el8.6.0+2786+d7c38b21 | | `jansi-native` | AlmaLinux:8 | All versions | 1.7-7.module_el8.6.0+2752+f1f3449e | | `jboss-interceptors-1.2-api` | AlmaLinux:8 | All versions | 1.0.0-8.module_el8.6.0+2752+f1f3449e | | `jcl-over-slf4j` | AlmaLinux:8 | All versions | 1.7.25-4.module_el8.6.0+2752+f1f3449e | | `jcl-over-slf4j` | AlmaLinux:8 | All versions | 1.7.28-3.module_el8.6.0+2786+d7c38b21 | | `jsoup` | AlmaLinux:8 | All versions | 1.11.3-3.module_el8.6.0+2752+f1f3449e | Products: Apache Httpclient, Netapp Active Iq Unified Manager, Netapp Snapcenter, Oracle Commerce Guided Search, Oracle Communications Cloud Native Core Service Communication Proxy, Oracle Data Integrator, Oracle Jd Edwards Enterpriseone Orchestrator, Oracle Jd Edwards Enterpriseone Tools, Oracle Nosql Database, Oracle Peoplesoft Enterprise Peopletools, Oracle Peoplesoft Enterprise Pt Peopletools, Oracle Primavera Unifier, Oracle Retail Customer Management and Segmentation Foundation, Oracle Spatial Studio, Oracle Sql Developer, Oracle Weblogic Server, Quarkus Quarkus. ## How do I fix CVE-2020-13956? Upgrade org.apache.httpcomponents:httpclient to a fixed version for your release line: 4.5.13 or 5.0.3. ## Is CVE-2020-13956 being exploited? There is no known exploitation of CVE-2020-13956 in the wild and no public exploit code. ## Other vulnerabilities in Netapp Active Iq Unified Manager - [CVE-2013-4366](https://insights.sbomify.com/CVE-2013-4366/): Hostname verification in Apache HttpClient 4.3 was disabled by default (critical 9.8) - [CVE-2026-71290](https://insights.sbomify.com/CVE-2026-71290/): Apache HttpComponents Client: TLS hostname verification silently disabled on the async transport (default config, MITM) (critical 9.1) - [CVE-2025-27820](https://insights.sbomify.com/CVE-2025-27820/): Apache HttpComponents: PSL (Public Suffix List) validation bypass (high 7.5) - [CVE-2026-40542](https://insights.sbomify.com/CVE-2026-40542/): Apache HttpClient accepts SCRAM-SHA-256 authentication without proper mutual authentication verification (high 7.3) - [CVE-2012-5783](https://insights.sbomify.com/CVE-2012-5783/): Improper Certificate Validation in Apache Commons HttpClient (medium 5.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2020-13956 and fix it if it is affected. What it is: CVE-2020-13956 is a medium-severity server-side request forgery vulnerability in Netapp Active Iq Unified Manager, published on 2 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-2020-13956 in the wild and no public exploit code. Affected packages and fixed versions: - org.apache.httpcomponents:httpclient (Maven): affected all versions; fixed in 4.5.13 - org.apache.httpcomponents:httpclient (Maven): affected all versions; fixed in 4.5.13 - org.apache.httpcomponents:httpclient (Maven): affected from 5.0.0; fixed in 5.0.3 - org.apache.httpcomponents:httpclient (Maven): affected from 5.0.0; fixed in 5.0.3 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-2020-13956/ (Markdown: https://insights.sbomify.com/CVE-2020-13956/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-13956 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-13956 - OSV: https://osv.dev/vulnerability/CVE-2020-13956 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-13956/ Summaries are generated and may contain mistakes; the official description above is the record.