GHSA-GWFQ-86J8-7QHV
Vulnerability from github – Published: 2026-08-05 19:59 – Updated: 2026-08-05 19:59Summary
When an RC API call triggers a panic (recovered by the job runner), the full Go stack trace is included in the JSON error response. This leaks internal file paths, Go module versions, goroutine state, and memory addresses to the API caller.
Details
The panic recovery in fs/rc/jobs/job.go:110-115:
func (j *Job) run(ctx context.Context, fn rc.Func, in rc.Params) {
defer func() {
if r := recover(); r != nil {
j.mu.Lock()
j.EndTime = time.Now()
j.Error = fmt.Sprintf("panic received: %v \n%s", r, string(debug.Stack()))
// ...
}
}()
The full debug.Stack() output is placed into j.Error, which is then returned in the HTTP response JSON.
PoC
Trigger a parse error by setting config path to a non-INI file, then calling dump:
curl -s -X POST http://localhost:5572/config/setpath \
-H "Content-Type: application/json" \
-d '{"path":"/etc/hostname"}'
curl -s -X POST http://localhost:5572/config/dump
Response includes:
{
"error": "panic received: fatal error: Failed to load config file \"/etc/hostname\": could not parse line: ... \ngoroutine 9 [running]:\nruntime/debug.Stack()\n\truntime/debug/stack.go:26 +0x64\ngithub.com/rclone/rclone/fs/rc/jobs.(*Job).run.func1()\n\tgithub.com/rclone/rclone/fs/rc/jobs/job.go:112 +0x34\n...",
"status": 500
}
Disclosed information includes:
- Full filesystem paths (github.com/rclone/rclone/fs/config/config.go:377)
- Go module versions (github.com/go-chi/chi/v5@v5.2.5)
- Go runtime version (from binary)
- Goroutine IDs and states
- Memory addresses (ASLR leak)
- File contents (first unparseable line of the target file)
Tested and confirmed on rclone v1.74.4.
Impact
Information disclosure that aids exploitation of other vulnerabilities. Stack traces reveal internal architecture, dependency versions (useful for known-CVE targeting), and memory layout. The error message also leaks partial file contents (the first line that fails INI parsing), which can be used alongside the arbitrary file read finding as a complementary file read primitive for non-INI files.
Affected Versions
All versions with RC API support through at least v1.74.4.
Remediation
Return a generic error message to the API caller. Log the full stack trace server-side only. Strip debug.Stack() from HTTP responses.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.74.4"
},
"package": {
"ecosystem": "Go",
"name": "github.com/rclone/rclone"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.75.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-209"
],
"github_reviewed": true,
"github_reviewed_at": "2026-08-05T19:59:55Z",
"nvd_published_at": null,
"severity": "LOW"
},
"details": "### Summary\n\nWhen an RC API call triggers a panic (recovered by the job runner), the full Go stack trace is included in the JSON error response. This leaks internal file paths, Go module versions, goroutine state, and memory addresses to the API caller.\n\n### Details\n\nThe panic recovery in `fs/rc/jobs/job.go:110-115`:\n\n```go\nfunc (j *Job) run(ctx context.Context, fn rc.Func, in rc.Params) {\n defer func() {\n if r := recover(); r != nil {\n j.mu.Lock()\n j.EndTime = time.Now()\n j.Error = fmt.Sprintf(\"panic received: %v \\n%s\", r, string(debug.Stack()))\n // ...\n }\n }()\n```\n\nThe full `debug.Stack()` output is placed into `j.Error`, which is then returned in the HTTP response JSON.\n\n### PoC\n\nTrigger a parse error by setting config path to a non-INI file, then calling dump:\n\n```bash\ncurl -s -X POST http://localhost:5572/config/setpath \\\n -H \"Content-Type: application/json\" \\\n -d \u0027{\"path\":\"/etc/hostname\"}\u0027 \n\ncurl -s -X POST http://localhost:5572/config/dump\n```\n\nResponse includes:\n\n```json\n{\n \"error\": \"panic received: fatal error: Failed to load config file \\\"/etc/hostname\\\": could not parse line: ... \\ngoroutine 9 [running]:\\nruntime/debug.Stack()\\n\\truntime/debug/stack.go:26 +0x64\\ngithub.com/rclone/rclone/fs/rc/jobs.(*Job).run.func1()\\n\\tgithub.com/rclone/rclone/fs/rc/jobs/job.go:112 +0x34\\n...\",\n \"status\": 500\n}\n```\n\n**Disclosed information includes:**\n- Full filesystem paths (`github.com/rclone/rclone/fs/config/config.go:377`)\n- Go module versions (`github.com/go-chi/chi/v5@v5.2.5`)\n- Go runtime version (from binary)\n- Goroutine IDs and states\n- Memory addresses (ASLR leak)\n- File contents (first unparseable line of the target file)\n\n**Tested and confirmed on rclone v1.74.4.**\n\n### Impact\n\nInformation disclosure that aids exploitation of other vulnerabilities. Stack traces reveal internal architecture, dependency versions (useful for known-CVE targeting), and memory layout. The error message also leaks partial file contents (the first line that fails INI parsing), which can be used alongside the arbitrary file read finding as a complementary file read primitive for non-INI files.\n\n### Affected Versions\n\nAll versions with RC API support through at least v1.74.4.\n\n### Remediation\n\nReturn a generic error message to the API caller. Log the full stack trace server-side only. Strip `debug.Stack()` from HTTP responses.",
"id": "GHSA-gwfq-86j8-7qhv",
"modified": "2026-08-05T19:59:55Z",
"published": "2026-08-05T19:59:55Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/rclone/rclone/security/advisories/GHSA-gwfq-86j8-7qhv"
},
{
"type": "WEB",
"url": "https://github.com/rclone/rclone/commit/ff43a1e3ae17627c80e523a0ca7445f96516d199"
},
{
"type": "PACKAGE",
"url": "https://github.com/rclone/rclone"
},
{
"type": "WEB",
"url": "https://github.com/rclone/rclone/releases/tag/v1.75.0"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "rclone: Verbose Stack Trace Disclosure in RC API Error Responses"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.