Kestra is an open-source, event-driven orchestration platform. Prior to 1.3.24, Kestra's custom Markdown parser in ui/src/utils/markdown_plugins/link.ts allows a user with permission to create or update a Flow description to inject JavaScript event-handler attributes through the custom [[link]] syntax, causing stored cross-site scripting when another user opens the description or information panel in the Flow list. This issue is fixed in version 1.3.24.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55839.json"
}"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55839.json"
[
{
"target": {
"file": "executor/src/main/java/io/kestra/executor/ExecutorService.java"
},
"deprecated": false,
"source": "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
"id": "CVE-2026-55839-ae852aa8",
"signature_version": "v1",
"digest": {
"threshold": 0.9,
"line_hashes": [
"140357562688538205345254706729617935184",
"304622577954603750062645385810567482955",
"172583391333871376895219175659680168624",
"183202715105275968527562296723581938117",
"297530466543600923085808142532015000696",
"166130564697929043102664410002815835326"
]
},
"signature_type": "Line"
},
{
"target": {
"file": "webserver/src/test/java/io/kestra/webserver/controllers/api/ExecutionControllerRunnerTest.java"
},
"deprecated": false,
"source": "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
"id": "CVE-2026-55839-b849bba4",
"signature_version": "v1",
"digest": {
"threshold": 0.9,
"line_hashes": [
"114665094312657875926090929902087966387",
"274801199915747080465899563020440974966",
"162451514141723112063978488641837120054",
"311266650890310641974077291142530475109",
"36923110329716295121989747954185703358",
"25482173696437418952014903161456696174"
]
},
"signature_type": "Line"
},
{
"target": {
"function": "shouldRunFlowableAfterExecutionWhenExecutionIsKilled",
"file": "webserver/src/test/java/io/kestra/webserver/controllers/api/ExecutionControllerRunnerTest.java"
},
"deprecated": false,
"source": "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
"id": "CVE-2026-55839-c95e9421",
"signature_version": "v1",
"digest": {
"length": 1430.0,
"function_hash": "290069323323167062483700325176558449078"
},
"signature_type": "Function"
},
{
"target": {
"function": "process",
"file": "executor/src/main/java/io/kestra/executor/ExecutorService.java"
},
"deprecated": false,
"source": "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
"id": "CVE-2026-55839-d6418229",
"signature_version": "v1",
"digest": {
"length": 1414.0,
"function_hash": "164146531972406519589227532778007779872"
},
"signature_type": "Function"
}
]
"2026-08-20T10:17:17Z"