{"schema":"threatline.record/2","record":{"id":"CVE-2026-61801","aliases":["GHSA-mjcv-p78q-w5fw","GO-2026-6686"],"summary":"github.com/moby/sys/user has a possible DoS via unbounded parsing of user and group database files","details":"A denial-of-service (DoS) vulnerability exists in `github.com/moby/sys/user` before v0.4.1 when parsing specially crafted user or group database files. An attacker able to supply a malicious `/etc/passwd` or `/etc/group`-style file may cause excessive memory consumption, potentially resulting in process termination due to Out Of Memory (OOM) conditions.\n\nThis issue is related to containerd [CVE-2026-47262] / [GHSA-jpcc-p29g-p8mq](https://github.com/containerd/containerd/security/advisories/GHSA-jpcc-p29g-p8mq), which describes one practical exploitation path through processing untrusted container image content. Applications using `github.com/moby/sys/user` to parse untrusted user or group database files may be similarly affected.\n\n### Impact\n\n`github.com/moby/sys/user` versions before v0.4.1 do not place sufficient limits on entries while parsing user and group database files. A specially crafted file may cause excessive memory consumption, potentially leading to process termination due to Out Of Memory (OOM) conditions.\n\nApplications that use `github.com/moby/sys/user` to parse user-supplied or otherwise untrusted `/etc/passwd` or `/etc/group` files may be affected. The severity depends on whether an attacker can influence the contents of files being parsed.\n\n### Patches\n\nThis issue is fixed in `github.com/moby/sys/user` v0.4.1. Users should upgrade to v0.4.1 or later.\n\n### Workarounds\n\nAvoid parsing attacker-controlled `/etc/passwd` or `/etc/group`-style files with affected versions of `github.com/moby/sys/user`.\n\nApplications that must process untrusted user or group database files should validate and limit accepted input before parsing. Upgrading to v0.4.1 or later is the recommended remediation.\n\n### References\n\n* containerd CVE-2026-47262 / GHSA-jpcc-p29g-p8mq: https://github.com/containerd/containerd/security/advisories/GHSA-jpcc-p29g-p8mq\n* Fix in `github.com/moby/sys/user`: https://github.com/moby/sys/user/commit/210d32ba2bcb4544ee968c7f31249fe59796e60b","categories":["Libraries & packages"],"product":"github.com/moby/sys/user","vendor":"moby","ecosystem":"go","affected_ranges":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-mjcv-p78q-w5fw","source_modified_at":"2026-10-08T16:08:35Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"go","name":"github.com/moby/sys/user"},"range":"<= 0.4.0"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-61801","source_modified_at":"2026-10-08T17:27:37.645Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"sys","vendor":"moby","versions":[{"version":"< 0.4.1","status":"affected"}],"defaultStatus":null},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-mjcv-p78q-w5fw","source_modified_at":"2026-10-19T21:40:47.349593935Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"Go","name":"github.com/moby/sys/user","purl":"pkg:golang/github.com/moby/sys/user"},"ranges":[{"events":[{"introduced":"0"},{"fixed":"0.4.1"}],"type":"SEMVER"}],"versions":[]}],"fixed_versions":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-mjcv-p78q-w5fw","source_modified_at":"2026-10-08T16:08:35Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"go","name":"github.com/moby/sys/user"},"version":"0.4.1"},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-mjcv-p78q-w5fw","source_modified_at":"2026-10-19T21:40:47.349593935Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"Go","name":"github.com/moby/sys/user","purl":"pkg:golang/github.com/moby/sys/user"},"version":"0.4.1"}],"cvss":5.5,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00113,"percentile":0.01351,"score_date":"2026-10-23"},"published_at":"2026-10-08T16:22:25.558Z","modified_at":"2026-10-19T21:40:47.349593935Z","provenance":[{"source":"GitHub Advisory Database","url":"https://github.com/advisories/GHSA-mjcv-p78q-w5fw","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-08T16:08:35Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-61801","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-08T17:27:37.645Z"},{"source":"OSV","url":"https://osv.dev/vulnerability/GHSA-mjcv-p78q-w5fw","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-19T21:40:47.349593935Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-61801","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["GitHub Advisory Database","CVE List","OSV","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/moby/sys/security/advisories/GHSA-mjcv-p78q-w5fw","tags":["x_refsource_CONFIRM"]},{"source":"CVE List","url":"https://github.com/moby/sys/pull/221","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/moby/sys/commit/85a71bbe1faa36c552a960e6a5f3d0cfb632fbbe","tags":["x_refsource_MISC"]},{"url":"https://github.com/advisories/GHSA-mjcv-p78q-w5fw","source":"GitHub Advisory Database"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-08T17:27:31.522788Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"ecosystem","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T21:40:47.349593935Z","content_hash":"439e7007c65831c16712e2a4f88067356d5432309065a0eb8ae5eaf872a9fe68"}}