# CVE-2012-2100: Integer overflow in n/a > A malformed ext4 filesystem can trigger an integer overflow in the Linux kernel, allowing attackers to cause a denial of service. - **Severity:** High 7.1 (`AV:N/AC:M/Au:N/C:N/I:N/A:C`) - **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:** 3 Jul 2012 - **Updated:** 6 Aug 2024 - **Also known as:** GHSA-cx5x-f2xm-m2cr, RHSA-2012:1445 ## What is CVE-2012-2100? CVE-2012-2100 is a high-severity vulnerability in Linux kernel, published on 3 Jul 2012. 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 The ext4_fill_flex_info function in fs/ext4/super.c in the Linux kernel before 3.2.2, on the x86 platform and unspecified other platforms, allows user-assisted remote attackers to trigger inconsistent filesystem-groups data and possibly cause a denial of service via a malformed ext4 filesystem containing a super block with a large FLEX_BG group size (aka s_log_groups_per_flex value). NOTE: this vulnerability exists because of an incomplete fix for CVE-2009-4307. Weakness: CWE-189 ## Which versions are affected by CVE-2012-2100? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `kernel` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE-devel` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug-devel` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debuginfo-common` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-devel` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-doc` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-headers` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen-devel` | Red Hat:enterprise_linux:5::client | All versions | 0:2.6.18-308.20.1.el5 | | `kernel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-PAE-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debug-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-debuginfo-common` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-doc` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-headers` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-kdump` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-kdump-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-kdump-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | | `kernel-xen-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-308.20.1.el5 | Products: Linux kernel. ## How do I fix CVE-2012-2100? Apply the vendor's patch. ## Is CVE-2012-2100 being exploited? There is no known exploitation of CVE-2012-2100 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2012-2100 and fix it if it is affected. What it is: CVE-2012-2100 is a high-severity vulnerability in Linux kernel, published on 3 Jul 2012. 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: There is no known exploitation of CVE-2012-2100 in the wild and no public exploit code. Affected product: Linux kernel. 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-2012-2100/ (Markdown: https://insights.sbomify.com/CVE-2012-2100/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2012-2100 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2012-2100 - OSV: https://osv.dev/vulnerability/CVE-2012-2100 --- From sbomify Insights: https://insights.sbomify.com/CVE-2012-2100/ Summaries are generated and may contain mistakes; the official description above is the record.