MEDIUM
CVE-2021-29136
CWE-20Published: April 6, 2021· Updated: Jun 17, 2026
5.5
CVSS v3.1
Official Description
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.
Technical Analysis
CVE-2021-29136 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in full integrity compromise (data manipulation), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityHigh
AvailabilityNone
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Affected Vendors & Products
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (6)
→
http://www.openwall.com/lists/oss-security/2021/04/06/2Mailing List · Patch · Third Party Advisory
→
https://github.com/opencontainers/umoci/commit/d9efc31daf2206f7d3fdb839863cf7a576a2eb57Patch · Third Party Advisory
→
https://github.com/opencontainers/umoci/security/advisories/GHSA-9m95-8hx6-7p9vThird Party Advisory
→
http://www.openwall.com/lists/oss-security/2021/04/06/2Mailing List · Patch · Third Party Advisory
→
https://github.com/opencontainers/umoci/commit/d9efc31daf2206f7d3fdb839863cf7a576a2eb57Patch · Third Party Advisory
→
https://github.com/opencontainers/umoci/security/advisories/GHSA-9m95-8hx6-7p9vThird Party Advisory
Quick Facts
CVE IDCVE-2021-29136
CVSS Score5.5 / 10
SeverityMEDIUM
WeaknessCWE-20
CISA KEVNo
Affected2 vendor(s)
PublishedApr 6, 2021
Related CVEs (CWE-20)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-29136 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.