Grav - Arbitrary File Upload via Avatar Endpoint
The Grav API plugin (getgrav/grav-plugin-api) 1.0.0 contains an unrestricted file upload vulnerability in the avatar upload endpoint (/api/v1/users/user/avatar). The endpoint validates only the client-declared MIME type (getClientMediaType) beginning with 'image/' and does not inspect the actual file content or restrict the resulting extension, allowing an authenticated user to store arbitrary content — including PHP code, SVG with embedded JavaScript, and polyglot payloads — under user/accounts/avatars/ with predictable filenames. Direct HTTP access to the stored files is blocked by .htaccess (returns 403), but the files persist on disk and could lead to remote code execution or stored XSS in the presence of a path traversal flaw or server misconfiguration. Fixed in 1.0.1.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-58654
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 16:39 UTC · Revision 1
Source evidence
Grav - Arbitrary File Upload via Avatar Endpoint
core-osv · Original sourcePublished 8 Jul 2026, 13:49 UTC
The Grav API plugin (getgrav/grav-plugin-api) 1.0.0 contains an unrestricted file upload vulnerability in the avatar upload endpoint (/api/v1/users/user/avatar). The endpoint validates only the client-declared MIME type (getClientMediaType) beginning with 'image/' and does not inspect the actual file content or restrict the resulting extension, allowing an authenticated user to store arbitrary content — including PHP code, SVG with embedded JavaScript, and polyglot payloads — under user/accounts/avatars/ with predictable filenames. Direct HTTP access to the stored files is blocked by .htaccess (returns 403), but the files persist on disk and could lead to remote code execution or stored XSS in the presence of a path traversal flaw or server misconfiguration. Fixed in 1.0.1.
osv:CVE-2026-58654
Complete source record
{
"id": "663c7182618d85a166596818540a301b9fbc5279db8463a8ef8f0ba097e59307",
"url": "https://osv.dev/vulnerability/CVE-2026-58654",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Grav - Arbitrary File Upload via Avatar Endpoint",
"summary": "The Grav API plugin (getgrav/grav-plugin-api) 1.0.0 contains an unrestricted file upload vulnerability in the avatar upload endpoint (/api/v1/users/user/avatar). The endpoint validates only the client-declared MIME type (getClientMediaType) beginning with 'image/' and does not inspect the actual file content or restrict the resulting extension, allowing an authenticated user to store arbitrary content — including PHP code, SVG with embedded JavaScript, and polyglot payloads — under user/accounts/avatars/ with predictable filenames. Direct HTTP access to the stored files is blocked by .htaccess (returns 403), but the files persist on disk and could lead to remote code execution or stored XSS in the presence of a path traversal flaw or server misconfiguration. Fixed in 1.0.1.",
"evidence": "osv:CVE-2026-58654",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-58654",
"aliases": [
"CVE-2026-58654",
"GHSA-xc64-vh46-vph6"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/getgrav/grav",
"type": "GIT",
"events": [
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"database_specific": {
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],
"modified": "2026-10-28T02:30:37.460143339Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58654.json",
"https://github.com/getgrav/grav/security/advisories/GHSA-xc64-vh46-vph6",
"https://nvd.nist.gov/vuln/detail/CVE-2026-58654",
"https://www.vulncheck.com/advisories/grav-arbitrary-file-upload-via-avatar-endpoint"
],
"provider_metadata": {
"cwe_ids": [
"CWE-434"
],
"cna_assigner": "VulnCheck",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58654.json"
}
},
"related_cves": [
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"evidence": "/id"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 504789,
"published_at": "2026-07-08T13:49:08.711+00:00"
}