CVE-2021-41103: Insufficiently restricted permissions on plugin directories
Vulnerability summary
CVE-2021-41103 is a high (CVSS 7.8) vulnerability in containerd. EPSS estimates a 0.52% chance of exploitation in the next 30 days, higher than 44.1% of scored vulnerabilities.
Not severe (CVSS 5.9, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 11 · Related 12Timeline
- 04-10-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
containerd is an open source container runtime with an emphasis on simplicity, robustness and portability. A bug was found in containerd where container root directories and some plugins had insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as setuid), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files. This vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability. Users unable to update should limit access to the host to trusted users. Update directory permission on container bundles directories.
CVSS metrics
11 scores · 8 sources · 3 versions- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · WolfiEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · ChainguardEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · AlpineEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- OSV · GoEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- NVDNIST5.9MediumCVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS trend
Probability
0.52%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.52% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian2 products
- containerd< 1.4.5~ds1-2+deb11u1 | < 1.5.7~ds1-1
- debian_linuxEOL11.0
Alpine1 product
- containerd≥ 1.5.0, < 1.5.7-r0
Chainguard1 product
- ctop< 0.7.7-r13
Containerd1 product
- containerd< 1.4.11 | ≥ 1.5.0, < 1.5.7
Fedoraproject1 product
- fedoraEOL34 | 35
Github.com/containerd1 product
- containerd< 1.4.11 | ≥ 1.5.0, < 1.5.7
Linuxfoundation1 product
- containerd< 1.4.11 | ≥ 1.5.0, < 1.5.7
Opensuse1 product
- containerd&distro=openSUSE Tumbleweed< 1.4.11-1.1
Ubuntu1 product
- containerd< 1.5.2-0ubuntu1~18.04.3 | < 1.5.2-0ubuntu1~20.04.3 | < 1.2.6-0ubuntu1~16.04.6+esm2 | < 1.5.5-0ubuntu3
Wolfi1 product
- ctop< 0.7.7-r13
10 vendors · 11 products
References
22 links- github.com/containerd/containerd/security/advisories/GHSA-c2h3-6mxw-7mvqREPORTAdvisoryWEBThird Party Advisory
- github.com/containerd/containerd/commit/5b46e404f6b9f661a205e28d59c982d3634148f8FIXWEBPatchThird Party Advisory
