# CVE-2020-25719: Auth bypass in samba > Samba AD DC allows domain compromise via Kerberos name-based authentication flaws when PAC is not strictly required. - **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** An administrator - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 18 Feb 2022 - **Updated:** 4 Aug 2024 - **Also known as:** ALPINE-CVE-2020-25719, ALSA-2021:5142, AZL-36995, AZL-8704, DEBIAN-CVE-2020-25719, ECHO-a223-d6f2-08e2, GHSA-882h-52g4-fpjv, RHSA-2021:5142, RHSA-2021:5195, RHSA-2022:0007, RHSA-2022:0076, RLSA-2021:5142, UBUNTU-CVE-2020-25719 ## What is CVE-2020-25719? CVE-2020-25719 is a high-severity authentication bypass vulnerability in Canonical Ubuntu Linux, published on 18 Feb 2022. An attacker needs administrator access to exploit it, with no action from the victim. ### Official description A flaw was found in the way Samba, as an Active Directory Domain Controller, implemented Kerberos name-based authentication. The Samba AD DC, could become confused about the user a ticket represents if it did not strictly require a Kerberos PAC and always use the SIDs found within. The result could include total domain compromise. Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization), CWE-287 (Improper Authentication) ## Which versions are affected by CVE-2020-25719? It affects 17 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `bind-dyndb-ldap` | AlmaLinux:8 | All versions | 11.6-2.module_el8.5.0+2603+92118e57 | | `custodia` | AlmaLinux:8 | All versions | 0.6.0-3.module_el8.5.0+2603+92118e57 | | `custodia` | AlmaLinux:8 | All versions | 0.6.0-3.module_el8.6.0+2881+2f24dc92 | | `ipa-client` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-client-common` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-client-epn` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-client-samba` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-common` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-healthcheck` | AlmaLinux:8 | All versions | 0.7-6.module_el8.5.0+2603+92118e57 | | `ipa-healthcheck-core` | AlmaLinux:8 | All versions | 0.7-6.module_el8.5.0+2603+92118e57 | | `ipa-python-compat` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-selinux` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-server` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-server-common` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-server-dns` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `ipa-server-trust-ad` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `opendnssec` | AlmaLinux:8 | All versions | 2.1.7-1.module_el8.5.0+2603+92118e57 | | `opendnssec` | AlmaLinux:8 | All versions | 2.1.7-1.module_el8.6.0+2881+2f24dc92 | | `python3-custodia` | AlmaLinux:8 | All versions | 0.6.0-3.module_el8.5.0+2603+92118e57 | | `python3-custodia` | AlmaLinux:8 | All versions | 0.6.0-3.module_el8.6.0+2881+2f24dc92 | | `python3-ipaclient` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `python3-ipalib` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `python3-ipaserver` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `python3-ipatests` | AlmaLinux:8 | All versions | 4.9.6-10.module_el8.5.0+2603+92118e57 | | `python3-jwcrypto` | AlmaLinux:8 | All versions | 0.5.0-1.module_el8.5.0+2603+92118e57 | | `python3-jwcrypto` | AlmaLinux:8 | All versions | 0.5.0-1.module_el8.6.0+2737+7e73ea90 | | `python3-jwcrypto` | AlmaLinux:8 | All versions | 0.5.0-1.module_el8.6.0+2881+2f24dc92 | | `python3-kdcproxy` | AlmaLinux:8 | All versions | 0.4-5.module_el8.5.0+2603+92118e57 | | `python3-kdcproxy` | AlmaLinux:8 | All versions | 0.4-5.module_el8.6.0+2881+2f24dc92 | | `python3-pyusb` | AlmaLinux:8 | All versions | 1.0.0-9.module_el8.5.0+2603+92118e57 | | `python3-pyusb` | AlmaLinux:8 | All versions | 1.0.0-9.module_el8.6.0+2737+7e73ea90 | | `python3-pyusb` | AlmaLinux:8 | All versions | 1.0.0-9.module_el8.6.0+2881+2f24dc92 | | `python3-qrcode` | AlmaLinux:8 | All versions | 5.1-12.module_el8.5.0+2603+92118e57 | | `python3-qrcode` | AlmaLinux:8 | All versions | 5.1-12.module_el8.6.0+2737+7e73ea90 | | `python3-qrcode` | AlmaLinux:8 | All versions | 5.1-12.module_el8.6.0+2881+2f24dc92 | | `python3-qrcode-core` | AlmaLinux:8 | All versions | 5.1-12.module_el8.5.0+2603+92118e57 | | `python3-qrcode-core` | AlmaLinux:8 | All versions | 5.1-12.module_el8.6.0+2737+7e73ea90 | | `python3-qrcode-core` | AlmaLinux:8 | All versions | 5.1-12.module_el8.6.0+2881+2f24dc92 | | `python3-yubico` | AlmaLinux:8 | All versions | 1.3.2-9.module_el8.5.0+2603+92118e57 | | `python3-yubico` | AlmaLinux:8 | All versions | 1.3.2-9.module_el8.6.0+2737+7e73ea90 | Products: Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux for Ibm Z Systems, Redhat Enterprise Linux for Ibm Z Systems Eus, Redhat Enterprise Linux for Power Big Endian, Redhat Enterprise Linux for Power Little Endian, Redhat Enterprise Linux for Power Little Endian Eus, Redhat Enterprise Linux for Scientific Computing, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Server Update Services for Sap Solutions, Redhat Enterprise Linux Workstation, Samba Samba. ## How do I fix CVE-2020-25719? Apply the vendor's patch. ## Is CVE-2020-25719 being exploited? There is no known exploitation of CVE-2020-25719 in the wild and no public exploit code. ## Other vulnerabilities in Canonical Ubuntu Linux - [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild) - [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild) - [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild) - [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild) - [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2020-25719 and fix it if it is affected. What it is: CVE-2020-25719 is a high-severity authentication bypass vulnerability in Canonical Ubuntu Linux, published on 18 Feb 2022. An attacker needs administrator access to exploit it, with no action from the victim. Exploitation: There is no known exploitation of CVE-2020-25719 in the wild and no public exploit code. Affected product: Canonical Ubuntu Linux. 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-2020-25719/ (Markdown: https://insights.sbomify.com/CVE-2020-25719/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-25719 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-25719 - OSV: https://osv.dev/vulnerability/CVE-2020-25719 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-25719/ Summaries are generated and may contain mistakes; the official description above is the record.