# CVE-2016-8743: Other in Apache HTTP Server > Attackers can exploit liberal whitespace handling to perform request smuggling, response splitting, and cache pollution in proxy or CGI chains. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/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:** 27 Jul 2017 - **Updated:** 16 Sep 2024 - **Also known as:** DEBIAN-CVE-2016-8743, DLA-841-1, DLA-841-2, GHSA-2rfh-2gh8-v9fq, RHSA-2017:1721, UBUNTU-CVE-2016-8743 ## What is CVE-2016-8743? CVE-2016-8743 is a high-severity vulnerability in Apache Http Server, published on 27 Jul 2017. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Apache HTTP Server, in all releases prior to 2.2.32 and 2.4.25, was liberal in the whitespace accepted from requests and sent in response lines and headers. Accepting these different behaviors represented a security concern when httpd participates in any chain of proxies or interacts with back-end application servers, either through mod_proxy or using conventional CGI mechanisms, and may result in request smuggling, response splitting and cache pollution. ## Which versions are affected by CVE-2016-8743? It affects 11 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `httpd` | Red Hat:enterprise_linux:6::client | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-debuginfo` | Red Hat:enterprise_linux:6::client | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-devel` | Red Hat:enterprise_linux:6::client | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-manual` | Red Hat:enterprise_linux:6::client | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-tools` | Red Hat:enterprise_linux:6::client | All versions | 0:2.2.15-60.el6_9.4 | | `mod_ssl` | Red Hat:enterprise_linux:6::client | All versions | 1:2.2.15-60.el6_9.4 | | `httpd` | Red Hat:enterprise_linux:6::computenode | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-debuginfo` | Red Hat:enterprise_linux:6::computenode | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-devel` | Red Hat:enterprise_linux:6::computenode | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-manual` | Red Hat:enterprise_linux:6::computenode | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-tools` | Red Hat:enterprise_linux:6::computenode | All versions | 0:2.2.15-60.el6_9.4 | | `mod_ssl` | Red Hat:enterprise_linux:6::computenode | All versions | 1:2.2.15-60.el6_9.4 | | `httpd` | Red Hat:enterprise_linux:6::server | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-debuginfo` | Red Hat:enterprise_linux:6::server | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-devel` | Red Hat:enterprise_linux:6::server | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-manual` | Red Hat:enterprise_linux:6::server | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-tools` | Red Hat:enterprise_linux:6::server | All versions | 0:2.2.15-60.el6_9.4 | | `mod_ssl` | Red Hat:enterprise_linux:6::server | All versions | 1:2.2.15-60.el6_9.4 | | `httpd` | Red Hat:enterprise_linux:6::workstation | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-debuginfo` | Red Hat:enterprise_linux:6::workstation | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-devel` | Red Hat:enterprise_linux:6::workstation | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-manual` | Red Hat:enterprise_linux:6::workstation | All versions | 0:2.2.15-60.el6_9.4 | | `httpd-tools` | Red Hat:enterprise_linux:6::workstation | All versions | 0:2.2.15-60.el6_9.4 | | `mod_ssl` | Red Hat:enterprise_linux:6::workstation | All versions | 1:2.2.15-60.el6_9.4 | Products: Apache Http Server, Debian Debian Linux, Netapp Clustered Data Ontap, Netapp Oncommand Unified Manager, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Workstation, Redhat Jboss Core Services. ## How do I fix CVE-2016-8743? Upgrade to a fixed version. ## Is CVE-2016-8743 being exploited? There is no known exploitation of CVE-2016-8743 in the wild and no public exploit code. ## Other vulnerabilities in Apache Http Server - [CVE-2021-42013](https://insights.sbomify.com/CVE-2021-42013/): Apache HTTP Server Path Traversal (critical 9.8, exploited in the wild) - [CVE-2024-38475](https://insights.sbomify.com/CVE-2024-38475/): Apache HTTP Server Improper Escaping of Output (critical 9.1, exploited in the wild) - [CVE-2021-40438](https://insights.sbomify.com/CVE-2021-40438/): Apache HTTP Server-Side Request Forgery (SSRF) (critical 9.0, exploited in the wild) - [CVE-2019-0211](https://insights.sbomify.com/CVE-2019-0211/): Apache HTTP Server Privilege Escalation (high 7.8, exploited in the wild) - [CVE-2021-41773](https://insights.sbomify.com/CVE-2021-41773/): Apache HTTP Server Path Traversal (high 7.5, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2016-8743 and fix it if it is affected. What it is: CVE-2016-8743 is a high-severity vulnerability in Apache Http Server, published on 27 Jul 2017. 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-2016-8743 in the wild and no public exploit code. Affected product: Apache Http Server. 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-2016-8743/ (Markdown: https://insights.sbomify.com/CVE-2016-8743/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2016-8743 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-8743 - OSV: https://osv.dev/vulnerability/CVE-2016-8743 --- From sbomify Insights: https://insights.sbomify.com/CVE-2016-8743/ Summaries are generated and may contain mistakes; the official description above is the record.