CVE-2020-5291: archlinux arch_linux Incorrect Use of Privileged APIs
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.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 31-03-2020PublishedVulnerability first disclosed.
- 04-08-2024Last 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- OSV · AlpineEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
- OSV · UbuntuEcosystem advisory · calculated7.2HighCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
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
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-648Incorrect Use of Privileged APIsThe product does not conform to the API requirements for a function call that requires extra privileges. This could allow attackers to gain privileges by causing the function to be called incorrectly.
- CWE-269Improper Privilege ManagementThe product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
Affected systems
Debian2 products
- bubblewrap< 0.4.1-1
- debian_linuxEOL10.0
Alpine1 product
- bubblewrap< 0.4.1-r0
Archlinux1 product
Centos1 product
- centosEOL7.0
Containers1 product
- bubblewrap< 0.4.1
Projectatomic1 product
- bubblewrap< 0.4.1
Ubuntu1 product
- bubblewrap< 0.4.0-1ubuntu4
7 vendors · 8 products
References
7 links- github.com/containers/bubblewrap/security/advisories/GHSA-j2qp-rvxj-43vjX Refsource CONFIRMREPORTMitigationThird Party Advisory
- github.com/containers/bubblewrap/commit/1f7e2ad948c051054b683461885a0215f1806240X Refsource MISCPatchThird Party Advisory