{
"id": "GHSA-f962-qm93-mj4c",
"aliases": [
"CVE-2026-55079"
],
"details": "### Summary\n\n`NewDataBuilder` in `provisionersdk/proto/dataupload.go` allocated a byte slice using the client-supplied `FileSize` from a `DataUpload` message without an upper-bound check. Although the DRPC wire limit is 4 MiB, the `FileSize` value itself was unconstrained\n\n### Impact\n\nAn authenticated user able to reach the provisioner daemon serve endpoint could send a roughly 50-byte message declaring a huge `FileSize` (for example 1 TiB), triggering an unrecoverable Go out-of-memory abort that terminates `coderd`. This is a single-message denial of service affecting the entire deployment.\n\n### Patches\n\nThe fix validates `FileSize` against an upper bound (`MaxFileSize = 100 MiB`) before allocation.\n\nThe fix was backported to all supported release lines:\n\n| Release line | Patched version |\n|---|---|\n| 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) |\n| 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) |\n| 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) |\n| 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) |\n\n### Workarounds\n\nRestrict access to the provisioner daemon serve endpoint to trusted provisioner daemon service accounts.\n\n### Resources\n\n- Fix: #25710\n\n### Credits\n\nCoder would like to thank Anthropic's Security Team (ANT-2026-22442) for independently disclosing this issue!",
"summary": "Coder's unbounded memory allocation in provisioner file upload allows authenticated denial of service",
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "2.34.0"
},
{
"fixed": "2.34.2"
}
]
}
],
"package": {
"name": "github.com/coder/coder/v2",
"ecosystem": "Go"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "2.33.0"
},
{
"fixed": "2.33.8"
}
]
}
],
"package": {
"name": "github.com/coder/coder/v2",
"ecosystem": "Go"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "2.30.0"
},
{
"fixed": "2.32.7"
}
]
}
],
"package": {
"name": "github.com/coder/coder/v2",
"ecosystem": "Go"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "2.24.0"
},
{
"fixed": "2.29.17"
}
]
}
],
"package": {
"name": "github.com/coder/coder/v2",
"ecosystem": "Go"
}
}
],
"modified": "2026-07-06T20:54:42Z",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H"
}
],
"published": "2026-07-06T20:54:41Z",
"references": [
{
"url": "https://github.com/coder/coder/security/advisories/GHSA-f962-qm93-mj4c",
"type": "WEB"
},
{
"url": "https://github.com/coder/coder/pull/25710",
"type": "WEB"
},
{
"url": "https://github.com/coder/coder",
"type": "PACKAGE"
}
],
"schema_version": "1.4.0",
"database_specific": {
"cwe_ids": [
"CWE-789"
],
"severity": "MODERATE",
"github_reviewed": true,
"nvd_published_at": null,
"github_reviewed_at": "2026-07-06T20:54:41Z"
}
}