Concourse login flow has an open redirect issue
Priority LOW 9CWE-601Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Active
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Spoofing
- Confidentiality · integrity · availability
- None · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-601.
Summary
Concourse is a container-based automation system written in Go. Prior to version 8.2.3, an attacker is able to craft and send a user a URL that will redirect the user from the Concourse web server to any other site. This could be used in a phishing attack to steal user's credentials. This has been fixed in 8.2.3. No known workarounds are available.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00526 44th percentileScored 2026-11-07
Fix Fixed concourse (concourse): 8.2.3github.com/concourse/concourse (Go): 1.6.1-0.20260526150512-ac60be5f0435
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| concourse | concourse | before 8.2.3 | 8.2.3 | Patch available | CNA |
| — | github.com/concourse/concourse (Go) | before 1.6.1-0.20260526150512-ac60be5f0435 | 1.6.1-0.20260526150512-ac60be5f0435 | Patch available | GHSA-8w27-c4vc-88q9 |
- concourse Vendorconcourse Affected before 8.2.3 Fixed in 8.2.3 Patch available CNA
- github.com/concourse/concourse (Go) Vendor— Affected before 1.6.1-0.20260526150512-ac60be5f0435 Fixed in 1.6.1-0.20260526150512-ac60be5f0435 Patch available GHSA-8w27-c4vc-88q9
Remediation
- Fix · CNA concourse (concourse) Fixed in 8.2.3
- Fix · GHSA-8w27-c4vc-88q9 github.com/concourse/concourse (Go) Fixed in 1.6.1-0.20260526150512-ac60be5f0435 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-49826
- 2026-10-03 Alias added: GHSA-8w27-c4vc-88q9
References
Sources
- CVE-2026-49826 · CVE Program
- CVE-2026-49826 · NVD
- FIRST EPSS
- GHSA-8w27-c4vc-88q9 · GitHub Advisory Database · CC BY 4.0
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