8.5

CVE-2020-5291: archlinux arch_linux Incorrect Use of Privileged APIs

CVSS: 8.5v2.0HighModified
AliasesALPINE-CVE-2020-5291UBUNTU-CVE-2020-5291DEBIAN-CVE-2020-5291
Published 31-03-2020Last modified 04-08-2024

Vulnerability summary

CVE-2020-5291 is a high (CVSS 8.5) Incorrect Use of Privileged APIs vulnerability in archlinux arch_linux. EPSS estimates a 0.90% chance of exploitation in the next 30 days, higher than 59% of scored vulnerabilities.

Overall risk
34/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.5/10
010
High · v2.0 (NVD)
EPSS score
0.90%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1

Timeline

  1. 31-03-2020
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

Bubblewrap (bwrap) before version 0.4.1, if installed in setuid mode and the kernel supports unprivileged user namespaces, then the `bwrap --userns2` option can be used to make the setuid process keep running as root while being traceable. This can in turn be used to gain root permissions. Note that this only affects the combination of bubblewrap in setuid mode (which is typically used when unprivileged user namespaces are not supported) and the support of unprivileged user namespaces. Known to be affected are: * Debian testing/unstable, if unprivileged user namespaces enabled (not default) * Debian buster-backports, if unprivileged user namespaces enabled (not default) * Arch if using `linux-hardened`, if unprivileged user namespaces enabled (not default) * Centos 7 flatpak COPR, if unprivileged user namespaces enabled (not default) This has been fixed in the 0.4.1 release, and all affected users should update.

CVSS metrics

6 scores · 5 sources · 2 versions

EPSS trend

Probability

0.90%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

-0.01 pp

From 0.91% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.90%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian2 products
Alpine1 product
  • bubblewrap< 0.4.1-r0
Archlinux1 product
Centos1 product
Containers1 product
Projectatomic1 product
Ubuntu1 product
  • bubblewrap< 0.4.0-1ubuntu4

7 vendors · 8 products

References

7 links