{"id":"BIT-rclone-2026-79783","revision":null,"records":[{"revision":"7a93bfec2b4a4e34af19dfc67f23fad7","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-79783","aliases":[],"title":"rclone before 1.74.4 Privilege Escalation via setuid Metadata","description":"rclone before 1.74.4 fails to mask special permission bits when applying source-supplied mode metadata in the local backend, allowing attackers to set setuid/setgid bits on attacker-controlled files. When copying with metadata preservation from an untrusted remote, attackers can plant a setuid binary that escalates privileges to root if rclone runs as root, or to the service account user otherwise.","state":0,"publishedAt":"2026-08-25T15:16:11.806+00:00","modifiedAt":"2026-08-25T16:11:49.885+00:00","affected":[{"ecosystem":"Vendor product","name":"rclone","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"rclone\",\n                    \"product\": \"rclone\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:golang/github.com/rclone/rclone\",\n                    \"versions\": [\n                        {\n                            \"version\": \"0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\",\n                            \"lessThan\": \"1.74.4\"\n                        },\n                        {\n                            \"version\": \"1.74.4\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","score":2,"severity":"LOW"},{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","score":3.6,"severity":"LOW"}],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-945v-v9p3-v5xw","https://www.vulncheck.com/advisories/rclone-before-privilege-escalation-via-setuid-metadata"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-79783","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-79783","identifiers":["CVE-2026-79783"]},"retained":false,"historicalAffected":[]},{"revision":"2e8f85c8c0154da7ba98fb6c44799759","observedAt":"2026-11-11T16:10:01.673+00:00","statement":{"source":"euvd","id":"EUVD-2026-65541","aliases":["CVE-2026-79783","GHSA-vqwj-943v-724g"],"title":"rclone before 1.74.4 fails to mask special permission bits when applying source-supplied mode metadata in the local backend, allowing attackers to set setuid/setgid bits on attacker-controlled files. When copying with metadata preservation …","description":"rclone before 1.74.4 fails to mask special permission bits when applying source-supplied mode metadata in the local backend, allowing attackers to set setuid/setgid bits on attacker-controlled files. When copying with metadata preservation from an untrusted remote, attackers can plant a setuid binary that escalates privileges to root if rclone runs as root, or to the service account user otherwise.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","score":2,"severity":null}],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-945v-v9p3-v5xw","https://www.vulncheck.com/advisories/rclone-before-privilege-escalation-via-setuid-metadata"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-65541","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Aug 25, 2026, 3:16:11 PM","dateUpdated":"Aug 25, 2026, 4:11:49 PM"},"relatedAdvisories":[],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-65541","identifiers":["EUVD-2026-65541","CVE-2026-79783","GHSA-vqwj-943v-724g"]},"retained":false,"historicalAffected":[]},{"revision":"54bb7c9ce3064d9e9c23757b9c212b42","observedAt":"2026-10-25T16:19:10.271+00:00","statement":{"source":"nvd","id":"CVE-2026-79783","aliases":[],"title":"rclone before 1.74.4 fails to mask special permission bits when applying source-supplied mode metadata in the local backend, allowing attackers to set setuid/setgid bits on attacker-controlled files. When copying with metadata preservation …","description":"rclone before 1.74.4 fails to mask special permission bits when applying source-supplied mode metadata in the local backend, allowing attackers to set setuid/setgid bits on attacker-controlled files. When copying with metadata preservation from an untrusted remote, attackers can plant a setuid binary that escalates privileges to root if rclone runs as root, or to the service account user otherwise.","state":0,"publishedAt":"2026-08-25T16:17:30.383+00:00","modifiedAt":"2026-09-10T20:46:19.78+00:00","affected":[],"metrics":[{"system":"CVSS 4.0 · disclosure@vulncheck.com · Secondary","vector":"CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","score":2,"severity":"LOW"},{"system":"CVSS 3.1 · disclosure@vulncheck.com · Secondary","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","score":3.6,"severity":"LOW"}],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-945v-v9p3-v5xw","https://www.vulncheck.com/advisories/rclone-before-privilege-escalation-via-setuid-metadata"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-79783","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Awaiting Analysis","weaknesses":["CWE-732"],"productCriteria":[],"sourceDates":{"published":"2026-08-25T16:17:30.383","lastModified":"2026-09-10T20:46:19.780"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-79783","identifiers":["CVE-2026-79783"]},"retained":false,"historicalAffected":[]},{"revision":"fab2e4c6c5f4400083726ca2147f0964","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-945v-v9p3-v5xw","aliases":["BIT-rclone-2026-79783","CVE-2026-79783","GO-2026-6190"],"title":"rclone local `--metadata` applies attacker-controlled mode/uid - setuid binary planted from an untrusted remote","description":"### Summary\nWhen writing an object with metadata, the local backend applies the source-supplied `mode`, `uid`, and `gid` verbatim: it parses `mode` as an octal integer and passes it straight into `os.Chmod(o.path, os.FileMode(umode))`, and passes `uid`/`gid` straight into `os.Chown`. The value is never masked to permission bits, so any value with Go's `ModeSetuid` (1<<23) or `ModeSetgid` (1<<22) bit set causes the setuid/setgid bit to be applied. Because both the file content and its metadata come from the (attacker-controlled) source remote, an attacker stores a binary of their choosing with `mode = 40000755` (and `uid = 0`); when the victim runs `rclone copy -M <remote>: /dest`, rclone writes the attacker's binary and makes it setuid. If the victim runs rclone as root (typical for system backup/restore), the `uid=0` chown plus setuid produces a root-owned setuid binary with attacker content — any local user then escalates to root. When rclone runs as a non-root service user, the planted setuid binary is owned by that user, giving any local user that user's privileges (lateral escalation / persistent backdoor).\n\n### Details\n`backend/local/metadata.go`, `writeMetadataToFile()`:\n```go\nuid, hasUID := o.parseMetadataInt(m, \"uid\", 10)\ngid, hasGID := o.parseMetadataInt(m, \"gid\", 10)\nif hasUID {\n    ...\n    err = os.Chown(o.path, uid, gid)        // source-controlled owner, no same-uid guard\n}\nmode, hasMode := o.parseMetadataInt(m, \"mode\", 8)\nif hasMode && mode >= 0 {\n    umode := uint(mode)\n    if umode <= math.MaxUint32 {\n        err = os.Chmod(o.path, os.FileMode(umode))   // <-- raw value; ModeSetuid/ModeSetgid NOT masked off\n    }\n}\n```\n`os.Chmod`/`os.FileMode` honor `ModeSetuid`/`ModeSetgid`/`ModeSticky`. There is no `&^ (os.ModeSetuid|os.ModeSetgid)` mask and no check that the source is trusted, so an attacker-chosen `mode` string sets those bits on the freshly written, attacker-controlled file. (Note: a legitimate local source reports `mode` in unix `st_mode` layout e.g. `0106755`, whose bit 1<<23 is unset, so honest copies happen to drop setuid — but the attacker supplies the Go-`FileMode` layout `40000755` directly, which sets it.)\n\n### PoC\n1) Get the official stable binary:\n```\ncurl -fsSLO https://downloads.rclone.org/v1.74.3/rclone-v1.74.3-linux-amd64.zip\nunzip -j rclone-v1.74.3-linux-amd64.zip '*/rclone' -d .      # ./rclone -> v1.74.3\n```\n2) Create a payload (the attacker-controlled binary content) and copy it with the malicious `mode` metadata:\n```\nmkdir -p msrc mdst && cp /bin/true msrc/payload\n./rclone copy -M --metadata-set mode=40000755 msrc mdst       # 40000755 = Go FileMode setuid|0755\n```\n3) Observe — the destination file is now setuid:\n```\nstat -c '%A %a' mdst/payload\n-rwsr-xr-x 4755                                               # 's' = setuid bit SET on attacker binary\n```\nVariants: `mode=20000755` → setgid (`-rwxr-sr-x`); `mode=60000755` → both (`-rwsr-sr-x`). With rclone run as root and the source object also carrying `uid=0`/`gid=0`, the file is chown'd root:root, yielding a root-owned setuid binary executable by any local user.\n\n\n### Impact\nA victim performing a metadata-preserving copy/restore (`-M`) from an untrusted or compromised remote installs an attacker-chosen executable with the setuid/setgid bit set. Run as root (system backup/restore, the common case for `--metadata`), this is a root-owned setuid root backdoor executable by any local user → local privilege escalation to root. Run as a non-root user, it is a setuid backdoor for that service account. The companion `uid`/`gid` application lets a root-run transfer also reassign ownership of written files arbitrarily.\n\n### Remediation\nMask special bits before applying mode from metadata — `os.Chmod(o.path, os.FileMode(umode).Perm())` (or `umode & 0o777`) — and do not honor setuid/setgid/sticky from source metadata; gate `uid`/`gid`/setuid application behind an explicit opt-in (e.g. `--local-metadata-set-ownership`) that is off by default, and document that `-M` from untrusted remotes must not restore privileged bits. Regression test: copying an object with `mode=40000755`/`uid=0` must produce a non-setuid, caller-owned file unless the opt-in is set.","state":0,"publishedAt":"2026-08-05T20:03:14+00:00","modifiedAt":"2026-09-25T14:25:48.3113108+00:00","affected":[{"ecosystem":"Go","name":"github.com/rclone/rclone","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"1.74.4"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"LOW"}],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-945v-v9p3-v5xw","https://github.com/rclone/rclone/commit/e58f09739a35774ca82b5211d2377ac0f2051500","https://github.com/rclone/rclone","https://github.com/rclone/rclone/releases/tag/v1.74.4"],"sourceUrl":"https://github.com/advisories/GHSA-945v-v9p3-v5xw","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-945v-v9p3-v5xw","identifiers":["GHSA-945v-v9p3-v5xw","BIT-rclone-2026-79783","CVE-2026-79783","GO-2026-6190"]},"retained":false,"historicalAffected":[]},{"revision":"d20a901d56d14e76b90697e19ff9ec85","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GO-2026-6190","aliases":["BIT-rclone-2026-79783","CVE-2026-79783","GHSA-945v-v9p3-v5xw"],"title":"Unsafe file permission restoration from metadata in github.com/rclone/rclone","description":"Unsafe file permission restoration from metadata in github.com/rclone/rclone","state":0,"publishedAt":"2026-08-18T16:38:10+00:00","modifiedAt":"2026-09-25T14:25:48.3113108+00:00","affected":[{"ecosystem":"Go","name":"github.com/rclone/rclone","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"1.74.4"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-945v-v9p3-v5xw","https://github.com/rclone/rclone/commit/e58f09739a35774ca82b5211d2377ac0f2051500","https://github.com/rclone/rclone/releases/tag/v1.74.4"],"sourceUrl":"https://osv.dev/vulnerability/GO-2026-6190","license":"OSV · upstream source license applies","key":"osv:GO-2026-6190","identifiers":["GO-2026-6190","BIT-rclone-2026-79783","CVE-2026-79783","GHSA-945v-v9p3-v5xw"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-12T11:55:28.1860721+00:00","complete":true,"records":1779,"lastAttemptAt":"2026-11-12T11:55:28.1860721+00:00","lastSuccessAt":"2026-11-12T11:55:28.4130785+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:28.4130791+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-64752486c567b55b31fb0d7225f5222bcd0019564ac0ac5f0649e242c7b19299-4a4604796d7c0adea2c1c677026f25a1e039e4a95710b02ad846575329daaa79","complete":true,"records":424651,"lastAttemptAt":"2026-11-12T11:53:33.8199862+00:00","lastSuccessAt":"2026-11-12T11:53:33.7811873+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:53:33.8199862+00:00","snapshotPublishedAt":"2026-11-12T11:27:22+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-0580dcc98aaa46a8935f8ff576f25037","complete":true,"records":13764,"lastAttemptAt":"2026-11-12T11:56:20.2141865+00:00","lastSuccessAt":"2026-11-12T11:56:20.209+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:56:20.209+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13817,"expectedIdentifiers":13817,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-12T11:55:28.1860721+00:00","complete":true,"records":1097,"lastAttemptAt":"2026-11-12T11:55:28.1860721+00:00","lastSuccessAt":"2026-11-12T11:55:28.4142299+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:28.4142304+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-ea8d0b9744d8407d9df5932458afeb6a","complete":false,"records":13764,"lastAttemptAt":"2026-11-12T11:55:53.6222651+00:00","lastSuccessAt":"2026-11-12T11:55:53.618+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:53.618+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13313,"expectedIdentifiers":13817,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-3562b6c78fd1bd0f0b55daf66a0926ae24f65e462df7f6d928caad458fc696bf","complete":true,"records":9947,"lastAttemptAt":"2026-11-12T11:55:28.0344457+00:00","lastSuccessAt":"2026-11-11T04:27:43.6877707+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:28.0344457+00:00","snapshotPublishedAt":"2026-11-11T03:32:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-456002455e0ab94bb92c95476d4e6d175c104cd594749982afd96c893728ecbc","complete":true,"records":2010,"lastAttemptAt":"2026-11-12T11:53:33.8856695+00:00","lastSuccessAt":"2026-11-11T02:36:58.1276999+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:53:33.8856695+00:00","snapshotPublishedAt":"2026-11-11T01:17:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-f46f74c6a30a9b6e4cfb481719c6d35521ebec2d53ebf163223d093ae587eb9d","complete":true,"records":3106,"lastAttemptAt":"2026-11-12T11:55:28.1484531+00:00","lastSuccessAt":"2026-11-12T09:55:31.1176285+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:28.1484531+00:00","snapshotPublishedAt":"2026-11-12T09:48:13+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-e59fd13399d7070c31f5f25102a6bcd537ccba91d773c8427fcf0d07ea0fe2d5","complete":true,"records":231700,"lastAttemptAt":"2026-11-12T11:55:27.8998515+00:00","lastSuccessAt":"2026-11-12T11:55:26.4268762+00:00","error":null,"lastVerifiedAt":"2026-11-12T11:55:27.8998515+00:00","snapshotPublishedAt":"2026-11-12T11:33:13+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}