Security readout for executives and security teams
Plain-English summary
A flaw in Kestra’s login protection lets an unauthenticated attacker reach normally protected API operations, create workflows, and run code. Default script plugins can turn this into root-level code execution inside the worker container, threatening workflow data, credentials, connected systems, and service availability.
Executive priority
Treat this as an emergency remediation and compromise-assessment issue. Prioritize Internet-accessible and business-critical Kestra deployments immediately, then all internally reachable instances. Because exploitation is documented and successful attacks can execute as root inside workers, upgrading alone should not replace retrospective log, container, credential, and downstream-system review.
Technical view
Kestra OSS AuthenticationFilter treats every request path ending in “/configs” as public instead of matching only the intended configuration endpoint. On affected releases, crafted API requests can therefore bypass Basic Auth. An attacker can create and execute workflows; default shell and Python script plugins enable code execution as root within the Kestra worker container.
Likely exposure
Affected Kestra OSS deployments are versions below 1.0.45 and versions from 1.1.0 through 1.3.20. Risk is greatest where Kestra APIs are reachable by untrusted networks. Internal deployments remain exposed to attackers with network access. The sources do not establish whether authentication mode, proxy rules, or plugin configuration reduce exposure in a specific deployment.
Exploitation context
CISA lists CVE-2026-49869 in the Known Exploited Vulnerabilities catalog, supporting active exploitation in the wild. Exploitation needs no credentials or user interaction and has low complexity. The supplied sources do not quantify campaign scale, identify threat actors, or describe confirmed victims.
Researcher notes
The core weakness is improper authentication caused by suffix-based path allowlisting, with command execution arising through legitimate workflow capabilities and default script plugins. The CVSS 3.1 score is 10.0 with network access, no privileges, no interaction, scope change, and high confidentiality, integrity, and availability impact. No exploit mechanics should be needed for defensive validation.
Mitigation direction
- Upgrade the 1.0 branch to Kestra 1.0.45 or later.
- Upgrade the 1.1–1.3 branch to Kestra 1.3.21 or later.
- Restrict Kestra API access to trusted networks until upgrading is complete.
- Review vendor guidance for any additional containment or incident-response recommendations.
Validation and detection
- Inventory Kestra versions and flag releases within the documented affected ranges.
- Confirm untrusted networks cannot reach Kestra APIs while remediation is pending.
- Verify the deployed version is 1.0.45, 1.3.21, or an appropriate later release.
- Review API and workflow audit records for unauthenticated creation or execution activity.
- Inspect worker containers and connected credentials for evidence of compromise.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-184: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-287: Credential and account abuse lookup
Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-78: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-918: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 10 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H3.96GitHub_MVulnerability scoring details
Base CVSS 3.1 score
10CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- Added to KEVCISA-ADP
CISA Known Exploited Vulnerabilities metadata lists this CVE as known exploited.
- ADP timelineCISA-ADP
CVE-2026-49869 added to CISA KEV
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2026-09-02T00:00:00.000Z: CVE-2026-49869 added to CISA KEV
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/kestra-io/kestra/security/advisories/GHSA-5vc5-wxxq-3fjxCVE reference, GitHub_M · x_refsource_CONFIRM
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-49869CVE reference, CISA-ADP · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.