CVE-2021-26937 Memory corruption in n/a
Critical 9.8
Published
Updated
Check this codebase for CVE-2021-26937 and fix it if it is affected.
What it is: CVE-2021-26937 is a critical memory corruption vulnerability in Debian Debian Linux, published on 9 Feb 2021. 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-2021-26937 in the wild and no public exploit code.
Affected product: Debian Debian 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-2021-26937/ (Markdown: https://insights.sbomify.com/CVE-2021-26937/index.md)
Remote attackers can cause a denial of service in GNU Screen via crafted UTF-8 sequences, leading to application crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-26937?
CVE-2021-26937 is a critical memory corruption vulnerability in Debian Debian Linux, published on 9 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.
Weakness: CWE-88
Which versions are affected by CVE-2021-26937?
It affects 3 products.
Linux distribution packages (40)
screen Red Hat:enterprise_linux:7::client | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen-debuginfo Red Hat:enterprise_linux:7::client | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen Red Hat:enterprise_linux:7::server | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen-debuginfo Red Hat:enterprise_linux:7::server | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen Red Hat:enterprise_linux:7::workstation | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen-debuginfo Red Hat:enterprise_linux:7::workstation | All versions | 0:4.1.0-0.27.20120314git3c2946.el7_9 |
screen Red Hat:rhel_aus:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen-debuginfo Red Hat:rhel_aus:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen Red Hat:rhel_e4s:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen-debuginfo Red Hat:rhel_e4s:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen Red Hat:rhel_tus:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen-debuginfo Red Hat:rhel_tus:7.7::server | All versions | 0:4.1.0-0.25.20120314git3c2946.el7_7.1 |
screen SUSE:Enterprise Storage 6 | All versions | 4.6.2-5.3.1 |
screen SUSE:HPE Helion OpenStack 8 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 12 SP2-LTSS | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 12 SP3-BCL | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 12 SP5 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server 15 SP1-BCL | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Server 15-LTSS | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 12 SP2 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 4.0.4-23.6.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 15 | All versions | 4.6.2-5.3.1 |
screen SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 4.6.2-5.3.1 |
screen SUSE:Manager Proxy 4.0 | All versions | 4.6.2-5.3.1 |
screen SUSE:Manager Retail Branch Server 4.0 | All versions | 4.6.2-5.3.1 |
screen SUSE:Manager Server 4.0 | All versions | 4.6.2-5.3.1 |
screen SUSE:OpenStack Cloud 7 | All versions | 4.0.4-23.6.1 |
screen SUSE:OpenStack Cloud 8 | All versions | 4.0.4-23.6.1 |
screen SUSE:OpenStack Cloud 9 | All versions | 4.0.4-23.6.1 |
Products include Debian Debian Linux, Fedoraproject Fedora, Gnu Screen.
How do I fix CVE-2021-26937?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-26937 being exploited?
There is no known exploitation of CVE-2021-26937 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2021-26937, AZL-7356, CLSA-2021-1618497131, CLSA-2021-1634925515, DEBIAN-CVE-2021-26937, DLA-2570-1 and 13 more.