# CVE-2025-62291: Integer overflow in strongSwan > A malicious EAP-MSCHAPv2 server can trigger an integer underflow leading to heap-based buffer overflow in strongSwan client, potentially allowing code execution or denial of service. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 16 Jan 2026 - **Updated:** 16 Jan 2026 - **Also known as:** ALPINE-CVE-2025-62291, AZL-74660, AZL-74766, DEBIAN-CVE-2025-62291, DLA-4359-1, DSA-6041-1, GHSA-p527-wjvq-vxg8, MGASA-2025-0272, OESA-2026-4070, OESA-2026-4071, SUSE-SU-2025:21167-1, SUSE-SU-2025:3834-1, SUSE-SU-2025:3855-1, SUSE-SU-2025:3856-1, SUSE-SU-2025:3857-1, SUSE-SU-2025:3873-1, SUSE-SU-2025:3904-1, UBUNTU-CVE-2025-62291, USN-7841-1, openSUSE-SU-2025:15681-1, openSUSE-SU-2025:20132-1 ## What is CVE-2025-62291? CVE-2025-62291 is a high-severity vulnerability in strongSwan, published on 16 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description In the eap-mschapv2 plugin (client-side) in strongSwan before 6.0.3, a malicious EAP-MSCHAPv2 server can send a crafted message of size 6 through 8, and cause an integer underflow that potentially results in a heap-based buffer overflow. Weakness: CWE-191 (Integer Underflow (Wrap or Wraparound)) ## Which versions are affected by CVE-2025-62291? | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `strongswan` | SUSE:Enterprise Storage 7.1 | All versions | 5.8.2-150200.11.45.1 | | `strongswan` | SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 5.8.2-150200.11.45.1 | | `strongswan` | SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | All versions | 5.9.11-150500.5.9.1 | | `strongswan` | SUSE:Linux Enterprise High Performance Computing 15 SP5-LTSS | All versions | 5.9.11-150500.5.9.1 | | `strongswan` | SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 5.9.12-150600.3.5.2 | | `strongswan` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 5.9.14-150700.3.3.1 | | `strongswan` | SUSE:Linux Enterprise Module for Package Hub 15 SP6 | All versions | 5.9.12-150600.3.5.2 | | `strongswan` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 5.9.14-150700.3.3.1 | | `strongswan` | SUSE:Linux Enterprise Server 12 SP5-LTSS | All versions | 5.1.3-26.29.1 | | `strongswan` | SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 5.8.2-150200.11.45.1 | | `strongswan` | SUSE:Linux Enterprise Server 15 SP4-LTSS | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | SUSE:Linux Enterprise Server 15 SP5-LTSS | All versions | 5.9.11-150500.5.9.1 | | `strongswan` | SUSE:Linux Enterprise Server 16.0 | All versions | 6.0.1-160000.3.1 | | `strongswan` | SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 | All versions | 5.1.3-26.29.1 | | `strongswan` | SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 5.8.2-150200.11.45.1 | | `strongswan` | SUSE:Linux Enterprise Server for SAP Applications 15 SP4 | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | SUSE:Linux Enterprise Server for SAP Applications 15 SP5 | All versions | 5.9.11-150500.5.9.1 | | `strongswan` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 6.0.1-160000.3.1 | | `strongswan` | SUSE:Linux Enterprise Workstation Extension 15 SP6 | All versions | 5.9.12-150600.3.5.2 | | `strongswan` | SUSE:Linux Enterprise Workstation Extension 15 SP7 | All versions | 5.9.14-150700.3.3.1 | | `strongswan` | SUSE:Manager Proxy LTS 4.3 | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | SUSE:Manager Server LTS 4.3 | All versions | 5.9.11-150400.19.20.1 | | `strongswan` | openSUSE:Leap 15.6 | All versions | 5.9.12-150600.3.5.2 | | `strongswan` | openSUSE:Leap 16.0 | All versions | 6.0.1-160000.3.1 | | `strongswan` | openSUSE:Tumbleweed | All versions | 6.0.3-1.1 | ## How do I fix CVE-2025-62291? Upgrade to a fixed version. ## Is CVE-2025-62291 being exploited? There is no known exploitation of CVE-2025-62291 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2025-62291 and fix it if it is affected. What it is: CVE-2025-62291 is a high-severity vulnerability in strongSwan, published on 16 Jan 2026. 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-2025-62291 in the wild and no public exploit code. Affected product: strongSwan. 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-2025-62291/ (Markdown: https://insights.sbomify.com/CVE-2025-62291/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2025-62291 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-62291 - OSV: https://osv.dev/vulnerability/CVE-2025-62291 --- From sbomify Insights: https://insights.sbomify.com/CVE-2025-62291/ Summaries are generated and may contain mistakes; the official description above is the record.