# CVE-2020-36024: Null dereference in n/a > Remote attackers can cause a denial of service in the Poppler PDF library via a crafted PDF file triggering a null pointer dereference. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Local or same network only - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 11 Aug 2023 - **Updated:** 3 Nov 2025 - **Also known as:** ALSA-2024:2979, DEBIAN-CVE-2020-36024, GHSA-4pj9-rq3x-vjw5, OESA-2025-2620, OESA-2025-2621, OESA-2025-2622, RHSA-2024:2979, RLSA-2024:2979, UBUNTU-CVE-2020-36024 ## What is CVE-2020-36024? CVE-2020-36024 is a medium-severity vulnerability in Freedesktop Poppler, published on 11 Aug 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. ### Official description An issue was discovered in freedesktop poppler version 20.12.1, allows remote attackers to cause a denial of service (DoS) via crafted .pdf file to FoFiType1C::convertToType1 function. Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2020-36024? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `poppler` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-cpp` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-cpp-devel` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-devel` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-glib` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-glib-devel` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-glib-doc` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-qt5` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-qt5-devel` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler-utils` | AlmaLinux:8 | All versions | 20.11.0-11.el8 | | `poppler` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-cpp-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-debugsource` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-glib` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-glib-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-qt5` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-qt5-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-utils` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-utils-debuginfo` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20.11.0-11.el8 | | `poppler-cpp` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-cpp-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-cpp-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-debugsource` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-glib-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-glib-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-glib-doc` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-qt5-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-qt5-devel` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler-utils-debuginfo` | Red Hat:enterprise_linux:8::crb | All versions | 0:20.11.0-11.el8 | | `poppler` | Rocky Linux:8 | All versions | 0:20.11.0-11.el8 | Products: Freedesktop Poppler. ## How do I fix CVE-2020-36024? Apply the vendor's patch. ## Is CVE-2020-36024 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36024 exists. ## Other vulnerabilities in Freedesktop Poppler - [CVE-2018-21009](https://insights.sbomify.com/CVE-2018-21009/): Integer overflow in n/a (high 8.8) - [CVE-2019-12293](https://insights.sbomify.com/CVE-2019-12293/): Memory corruption in n/a (high 8.8) - [CVE-2019-10872](https://insights.sbomify.com/CVE-2019-10872/): Memory corruption in n/a (high 8.8) - [CVE-2019-9543](https://insights.sbomify.com/CVE-2019-9543/): Denial of service in n/a (high 8.8) - [CVE-2019-9545](https://insights.sbomify.com/CVE-2019-9545/): Denial of service in n/a (high 8.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2020-36024 and fix it if it is affected. What it is: CVE-2020-36024 is a medium-severity vulnerability in Freedesktop Poppler, published on 11 Aug 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36024 exists. Affected product: Freedesktop Poppler. 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-2020-36024/ (Markdown: https://insights.sbomify.com/CVE-2020-36024/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-36024 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-36024 - OSV: https://osv.dev/vulnerability/CVE-2020-36024 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-36024/ Summaries are generated and may contain mistakes; the official description above is the record.