{"id":"CVE-2026-29050","summary":"melange has Path Traversal When Resolving External Pipelines via Unvalidated pipeline[].uses","details":"melange allows users to build apk packages using declarative pipelines. Starting in version 0.32.0 and prior to version 0.43.4, an attacker who can influence a melange configuration file — for example through pull-request-driven CI or build-as-a-service scenarios — could set `pipeline[].uses` to a value containing `../` sequences or an absolute path. The `(*Compiled).compilePipeline` function in `pkg/build/compile.go` passed `uses` directly to `filepath.Join(pipelineDir, uses + \".yaml\")` without validating the value, so the resolved path could escape each `--pipeline-dir` and read an arbitrary YAML-parseable file visible to the melange process. Because the loaded file is subsequently interpreted as a melange pipeline and its `runs:` block is executed via `/bin/sh -c` in the build sandbox, this additionally allowed shell commands sourced from an out-of-tree file to run during the build, bypassing the review boundary that normally covers the in-tree pipeline definition. The issue is fixed in melange v0.43.4 via commit 5829ca4. The fix rejects `uses` values that are absolute paths or contain `..`, and verifies (via `filepath.Rel` after `filepath.Clean`) that the resolved target remains within the pipeline directory. As a workaround, only run `melange build` against configuration files from trusted sources. In CI systems that build user-supplied melange configs, gate builds behind manual review of `pipeline[].uses` values and reject any containing `..` or leading `/`.","aliases":["GHSA-98f2-w9h9-7fp9","GO-2026-5279"],"modified":"2026-08-12T03:51:31.427313611Z","published":"2026-04-23T23:58:39.668Z","related":["openSUSE-SU-2026:21483-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29050.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-22"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29050.json"},{"type":"ADVISORY","url":"https://github.com/chainguard-dev/melange/security/advisories/GHSA-98f2-w9h9-7fp9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-29050"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/chainguard-dev/melange","events":[{"introduced":"5307b483f36d3099f17a1db338779be6a5f0b9cf"},{"fixed":"ba26216d9671b7fd8e2696a3a217f441f2e04b05"}],"database_specific":{"cpe":"cpe:2.3:a:chainguard:melange:*:*:*:*:*:go:*:*","extracted_events":[{"introduced":"0.32.0"},{"fixed":"0.43.4"}],"source":["AFFECTED_FIELD","CPE_RANGE"]}}],"versions":["v0.43.3","v0.43.2","v0.43.1","v0.43.0","v0.42.0","v0.41.1","v0.41.0","v0.40.5","v0.40.4","v0.40.3","v0.40.2","v0.40.1","v0.40.0","v0.39.0","v0.38.1","v0.38.0","v0.37.5","v0.37.4","v0.37.3","v0.37.2","v0.37.1","v0.37.0","v0.36.0","v0.35.1","v0.35.0","v0.34.3","v0.34.2","v0.34.1","v0.34.0","v0.33.2","v0.33.1","v0.33.0","v0.32.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-29050.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N"}]}