# CVE-2023-20264: Open redirect in Cisco Adaptive Security Appliance (ASA) Software > An attacker can intercept SAML assertions via a modified login URL to hijack remote access VPN sessions and gain network access. - **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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:** No - **Published:** 1 Nov 2023 - **Updated:** 2 Aug 2024 - **Also known as:** GHSA-3gjh-276x-542v ## What is CVE-2023-20264? CVE-2023-20264 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software, published on 1 Nov 2023. 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 A vulnerability in the implementation of Security Assertion Markup Language (SAML) 2.0 single sign-on (SSO) for remote access VPN in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to intercept the SAML assertion of a user who is authenticating to a remote access VPN session. This vulnerability is due to insufficient validation of the login URL. An attacker could exploit this vulnerability by persuading a user to access a site that is under the control of the attacker, allowing the attacker to modify the login URL. A successful exploit could allow the attacker to intercept a successful SAML assertion and use that assertion to establish a remote access VPN session toward the affected device with the identity and permissions of the hijacked user, resulting in access to the protected network. Weakness: CWE-601 (URL Redirection to Untrusted Site) ## Which versions are affected by CVE-2023-20264? It affects 2 products. Products: Cisco Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense. ## How do I fix CVE-2023-20264? No fix has been published for CVE-2023-20264 yet. Limit exposure of the affected software until one is available. ## Is CVE-2023-20264 being exploited? There is no known exploitation of CVE-2023-20264 in the wild and no public exploit code. ## Other vulnerabilities in Cisco Adaptive Security Appliance Software - [CVE-2025-20333](https://insights.sbomify.com/CVE-2025-20333/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow (critical 9.9, exploited in the wild) - [CVE-2016-6366](https://insights.sbomify.com/CVE-2016-6366/): Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow (high 8.8, exploited in the wild) - [CVE-2026-20349](https://insights.sbomify.com/CVE-2026-20349/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection (high 8.6, exploited in the wild) - [CVE-2024-20353](https://insights.sbomify.com/CVE-2024-20353/): Cisco ASA and FTD Denial of Service (high 8.6, exploited in the wild) - [CVE-2016-6367](https://insights.sbomify.com/CVE-2016-6367/): Cisco Adaptive Security Appliance (ASA) CLI Remote Code Execution (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-20264 and fix it if it is affected. What it is: CVE-2023-20264 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software, published on 1 Nov 2023. 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-2023-20264 in the wild and no public exploit code. Affected product: Cisco Adaptive Security Appliance Software. 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-2023-20264/ (Markdown: https://insights.sbomify.com/CVE-2023-20264/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20264 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20264 - OSV: https://osv.dev/vulnerability/CVE-2023-20264 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-20264/ Summaries are generated and may contain mistakes; the official description above is the record.