# CVE-2021-33516: Server-side request forgery in n/a > Remote attackers can exploit DNS rebinding in GUPnP to trick browsers into accessing local UPnP services, enabling data exfiltration or modification. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 24 May 2021 - **Updated:** 3 Aug 2024 - **Also known as:** ALSA-2021:2363, CLSA-2026-1791546292, DEBIAN-CVE-2021-33516, GHSA-mqgp-2h56-fx4q, MGASA-2021-0321, OESA-2021-1272, RHSA-2021:2363, RHSA-2021:2417, RHSA-2021:2422, RHSA-2021:2459, RLSA-2021:2363, SUSE-SU-2021:2080-1, SUSE-SU-2021:2153-1, UBUNTU-CVE-2021-33516, USN-4970-1, openSUSE-SU-2021:0917-1, openSUSE-SU-2021:2153-1 ## What is CVE-2021-33516? CVE-2021-33516 is a high-severity server-side request forgery vulnerability in n/a, published on 24 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official description An issue was discovered in GUPnP before 1.0.7 and 1.1.x and 1.2.x before 1.2.5. It allows DNS rebinding. A remote web server can exploit this vulnerability to trick a victim's browser into triggering actions against local UPnP services implemented using this library. Depending on the affected service, this could be used for data exfiltration, data tempering, etc. ## Which versions are affected by CVE-2021-33516? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `gupnp` | AlmaLinux:8 | All versions | 1.0.6-2.el8_4 | | `gupnp-devel` | AlmaLinux:8 | All versions | 1.0.6-2.el8_4 | | `gupnp` | Red Hat:enterprise_linux:7::client | All versions | 0:1.0.2-6.el7_9 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:7::client | All versions | 0:1.0.2-6.el7_9 | | `gupnp-devel` | Red Hat:enterprise_linux:7::client | All versions | 0:1.0.2-6.el7_9 | | `gupnp-docs` | Red Hat:enterprise_linux:7::client | All versions | 0:1.0.2-6.el7_9 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:7::computenode | All versions | 0:1.0.2-6.el7_9 | | `gupnp-devel` | Red Hat:enterprise_linux:7::computenode | All versions | 0:1.0.2-6.el7_9 | | `gupnp-docs` | Red Hat:enterprise_linux:7::computenode | All versions | 0:1.0.2-6.el7_9 | | `gupnp` | Red Hat:enterprise_linux:7::server | All versions | 0:1.0.2-6.el7_9 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:1.0.2-6.el7_9 | | `gupnp-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:1.0.2-6.el7_9 | | `gupnp-docs` | Red Hat:enterprise_linux:7::server | All versions | 0:1.0.2-6.el7_9 | | `gupnp` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.0.2-6.el7_9 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.0.2-6.el7_9 | | `gupnp-devel` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.0.2-6.el7_9 | | `gupnp-docs` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.0.2-6.el7_9 | | `gupnp` | Red Hat:enterprise_linux:8::appstream | All versions | 0:1.0.6-2.el8_4 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:1.0.6-2.el8_4 | | `gupnp-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:1.0.6-2.el8_4 | | `gupnp-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:1.0.6-2.el8_4 | | `gupnp-debugsource` | Red Hat:enterprise_linux:8::crb | All versions | 0:1.0.6-2.el8_4 | | `gupnp-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:1.0.6-2.el8_4 | | `gupnp` | Red Hat:rhel_eus:8.1::appstream | All versions | 0:1.0.3-3.el8_1 | | `gupnp-debuginfo` | Red Hat:rhel_eus:8.1::appstream | All versions | 0:1.0.3-3.el8_1 | | `gupnp-debugsource` | Red Hat:rhel_eus:8.1::appstream | All versions | 0:1.0.3-3.el8_1 | | `gupnp-debuginfo` | Red Hat:rhel_eus:8.1::crb | All versions | 0:1.0.3-3.el8_1 | | `gupnp-debugsource` | Red Hat:rhel_eus:8.1::crb | All versions | 0:1.0.3-3.el8_1 | | `gupnp-devel` | Red Hat:rhel_eus:8.1::crb | All versions | 0:1.0.3-3.el8_1 | | `gupnp` | Red Hat:rhel_eus:8.2::appstream | All versions | 0:1.0.3-3.el8_2 | | `gupnp-debuginfo` | Red Hat:rhel_eus:8.2::appstream | All versions | 0:1.0.3-3.el8_2 | | `gupnp-debugsource` | Red Hat:rhel_eus:8.2::appstream | All versions | 0:1.0.3-3.el8_2 | | `gupnp-debuginfo` | Red Hat:rhel_eus:8.2::crb | All versions | 0:1.0.3-3.el8_2 | | `gupnp-debugsource` | Red Hat:rhel_eus:8.2::crb | All versions | 0:1.0.3-3.el8_2 | | `gupnp-devel` | Red Hat:rhel_eus:8.2::crb | All versions | 0:1.0.3-3.el8_2 | | `gupnp` | Rocky Linux:8 | All versions | 0:1.0.6-2.el8_4 | | `gupnp` | SUSE:Linux Enterprise Module for Desktop Applications 15 SP2 | All versions | 1.2.2-3.3.1 | | `gupnp` | SUSE:Linux Enterprise Module for Desktop Applications 15 SP3 | All versions | 1.2.2-3.3.1 | | `gupnp` | SUSE:Linux Enterprise Module for Package Hub 15 SP2 | All versions | 1.2.2-3.3.1 | | `gupnp` | SUSE:Linux Enterprise Module for Package Hub 15 SP3 | All versions | 1.2.2-3.3.1 | Products: Gnome Gupnp. ## How do I fix CVE-2021-33516? Upgrade to a fixed version. ## Is CVE-2021-33516 being exploited? There is no known exploitation of CVE-2021-33516 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2021-33516 and fix it if it is affected. What it is: CVE-2021-33516 is a high-severity server-side request forgery vulnerability in n/a, published on 24 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2021-33516 in the wild and no public exploit code. Affected product: n/a. 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-2021-33516/ (Markdown: https://insights.sbomify.com/CVE-2021-33516/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33516 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33516 - OSV: https://osv.dev/vulnerability/CVE-2021-33516 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-33516/ Summaries are generated and may contain mistakes; the official description above is the record.