CVE-2021-20201 Denial of service in spice
Medium 5.3
Published
Updated
Check this codebase for CVE-2021-20201 and fix it if it is affected.
What it is: CVE-2021-20201 is a medium-severity denial of service vulnerability in Redhat Enterprise Linux, published on 28 May 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-2021-20201 in the wild and no public exploit code.
Affected product: Redhat Enterprise 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-2021-20201/ (Markdown: https://insights.sbomify.com/CVE-2021-20201/index.md)
Remote attackers can cause denial of service via CPU consumption by performing many renegotiations in a single connection.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-20201?
CVE-2021-20201 is a medium-severity denial of service vulnerability in Redhat Enterprise Linux, published on 28 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw was found in spice in versions before 0.14.92. A DoS tool might make it easier for remote attackers to cause a denial of service (CPU consumption) by performing many renegotiations within a single connection.
Weakness: CWE-400
Which versions are affected by CVE-2021-20201?
It affects 2 products.
Linux distribution packages (32)
spice-server AlmaLinux:8 | All versions | 0.14.3-4.el8 |
spice-server-devel AlmaLinux:8 | All versions | 0.14.3-4.el8 |
spice Red Hat:enterprise_linux:8::appstream | All versions | 0:0.14.3-4.el8 |
spice-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 0:0.14.3-4.el8 |
spice-server Red Hat:enterprise_linux:8::appstream | All versions | 0:0.14.3-4.el8 |
spice-server-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:0.14.3-4.el8 |
spice-debugsource Red Hat:enterprise_linux:8::crb | All versions | 0:0.14.3-4.el8 |
spice-server-debuginfo Red Hat:enterprise_linux:8::crb | All versions | 0:0.14.3-4.el8 |
spice-server-devel Red Hat:enterprise_linux:8::crb | All versions | 0:0.14.3-4.el8 |
spice Rocky Linux:8 | All versions | 0:0.14.3-4.el8 |
spice SUSE:HPE Helion OpenStack 8 | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Micro 5.0 | All versions | 0.14.2-3.6.1 |
spice SUSE:Linux Enterprise Micro 5.2 | All versions | 0.14.3-150300.3.3.1 |
spice SUSE:Linux Enterprise Module for Server Applications 15 SP2 | All versions | 0.14.2-3.6.1 |
spice SUSE:Linux Enterprise Module for Server Applications 15 SP3 | All versions | 0.14.3-150300.3.3.1 |
spice SUSE:Linux Enterprise Server 12 SP3-BCL | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server 12 SP3-LTSS | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server 12 SP4-LTSS | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server 12 SP5 | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server for SAP Applications 12 SP3 | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server for SAP Applications 12 SP4 | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 0.12.8-18.1 |
spice SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 0.12.8-18.1 |
spice SUSE:OpenStack Cloud 8 | All versions | 0.12.8-18.1 |
spice SUSE:OpenStack Cloud 9 | All versions | 0.12.8-18.1 |
spice SUSE:OpenStack Cloud Crowbar 8 | All versions | 0.12.8-18.1 |
spice SUSE:OpenStack Cloud Crowbar 9 | All versions | 0.12.8-18.1 |
spice openSUSE:Leap 15.2 | All versions | 0.14.2-lp152.2.6.1 |
spice openSUSE:Leap 15.3 | All versions | 0.14.3-150300.3.3.1 |
spice openSUSE:Leap Micro 5.2 | All versions | 0.14.3-150300.3.3.1 |
spice openSUSE:Tumbleweed | All versions | 0.15.2-2.1 |
spice-gtk openSUSE:Tumbleweed | All versions | 0.41-3.1 |
Products include Redhat Enterprise Linux, Spice Project Spice.
How do I fix CVE-2021-20201?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-20201 being exploited?
There is no known exploitation of CVE-2021-20201 in the wild and no public exploit code.
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- CVE-2021-20325 Missing fixes for CVE-2021-40438 and CVE-2021-26691 in the versions of httpd, as shipped in Red Hat Enterprise Linux 8.5.0, causes a securit
- CVE-2018-25011 Memory corruption in libwebp
- CVE-2018-25014 Other in libwebp
- CVE-2014-3585 Supply chain in redhat-upgrade-tool
Sources
Also known as ALPINE-CVE-2021-20201, ALSA-2021:1924, CLSA-2026-1778489013, DEBIAN-CVE-2021-20201, GHSA-f3pm-m5m9-45gw, MGASA-2021-0405 and 11 more.