CVE-2026-55839

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Source
https://cve.org/CVERecord?id=CVE-2026-55839
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55839.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-55839
Aliases
Published
2026-08-18T15:27:18Z
Modified
2026-09-18T08:08:46Z
Severity
  • 8.7 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N CVSS Calculator
Summary
Kestra: Stored XSS via custom Markdown [[link]] attribute injection
Details

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.

Database specific 
{
    "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"
}
References

Affected packages

Git / github.com/kestra-io/kestra

Affected ranges

Type
GIT
Repo
https://github.com/kestra-io/kestra
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
6c8e6d099ed172cbb6b003b7fb30b7bb1f8f710e
Fixed
51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "0"
        },
        {
            "fixed":  "1.3.24"
        }
    ],
    "source":  [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

v0.*
v0.0.1234
v0.19.0
v0.7.0
v0.7.1
v0.8.0
v0.8.1
v0.9.0
v0.9.1
v1.*
v1.3.0
v1.3.0-rc0
v1.3.0-rc1
v1.3.1
v1.3.11
v1.3.13
v1.3.14
v1.3.15
v1.3.16
v1.3.17
v1.3.18
v1.3.19
v1.3.2
v1.3.20
v1.3.21
v1.3.22
v1.3.23
v1.3.3
v1.3.4
v1.3.5
v1.3.6
v1.3.7
v1.3.8
v1.3.9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55839.json"
vanir_signatures 
[
    {
        "deprecated":  false,
        "digest":  {
            "line_hashes":  [
                "140357562688538205345254706729617935184",
                "304622577954603750062645385810567482955",
                "172583391333871376895219175659680168624",
                "183202715105275968527562296723581938117",
                "297530466543600923085808142532015000696",
                "166130564697929043102664410002815835326"
            ],
            "threshold":  0.9
        },
        "id":  "CVE-2026-55839-ae852aa8",
        "signature_type":  "Line",
        "signature_version":  "v1",
        "source":  "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
        "target":  {
            "file":  "executor/src/main/java/io/kestra/executor/ExecutorService.java"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "line_hashes":  [
                "114665094312657875926090929902087966387",
                "274801199915747080465899563020440974966",
                "162451514141723112063978488641837120054",
                "311266650890310641974077291142530475109",
                "36923110329716295121989747954185703358",
                "25482173696437418952014903161456696174"
            ],
            "threshold":  0.9
        },
        "id":  "CVE-2026-55839-b849bba4",
        "signature_type":  "Line",
        "signature_version":  "v1",
        "source":  "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
        "target":  {
            "file":  "webserver/src/test/java/io/kestra/webserver/controllers/api/ExecutionControllerRunnerTest.java"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "function_hash":  "290069323323167062483700325176558449078",
            "length":  1430
        },
        "id":  "CVE-2026-55839-c95e9421",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
        "target":  {
            "file":  "webserver/src/test/java/io/kestra/webserver/controllers/api/ExecutionControllerRunnerTest.java",
            "function":  "shouldRunFlowableAfterExecutionWhenExecutionIsKilled"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "function_hash":  "164146531972406519589227532778007779872",
            "length":  1414
        },
        "id":  "CVE-2026-55839-d6418229",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/kestra-io/kestra/commit/51fcc9e4e7b69a706e10f77aaf1fdf56b7eb6630",
        "target":  {
            "file":  "executor/src/main/java/io/kestra/executor/ExecutorService.java",
            "function":  "process"
        }
    }
]
vanir_signatures_modified 
"2026-09-18T08:08:46Z"