CVE-2021-29136

5.5 mediumEPSS 0.3%

Medium (5.5). EPSS 0.3% chance of exploitation in the next 30 days. Fixed in github.com/opencontainers/umoci 0.4.7.

Open Container Initiative umoci before 0.4.7 allows attackers to overwrite arbitrary host paths via a crafted image that causes symlink traversal when "umoci unpack" or "umoci raw unpack" is used.

Severity

CVSS 3.1

5.5 medium

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

EPSS: 0.3% chance of exploitation in the next 30 days; higher than 27% of CVEs (scores of 2026-10-31)
CWE: CWE-20
Published: 2021-04-06
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

linuxfoundation:umoci
sylabs:singularity

Packages (OSV)

Advisory	Ecosystem	Package	Affected	Fixed in
GHSA-9m95-8hx6-7p9v	Go	github.com/opencontainers/umoci	<0.4.7	0.4.7
GO-2022-0815	Go	github.com/opencontainers/umoci	<0.4.7	0.4.7

References

http://www.openwall.com/lists/oss-security/2021/04/06/2
https://github.com/opencontainers/umoci/commit/d9efc31daf2206f7d3fdb839863cf7a576a2eb57
https://github.com/opencontainers/umoci/security/advisories/GHSA-9m95-8hx6-7p9v
http://www.openwall.com/lists/oss-security/2021/04/06/2
https://github.com/opencontainers/umoci/commit/d9efc31daf2206f7d3fdb839863cf7a576a2eb57

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