CVE-2020-5409
Concourse Open Redirect in the /sky/login endpoint
CVE-2020-5409 is a high vulnerability (CVSS 7.6) in Pivotal Concourse, published May 13, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.91%, the 59th percentile. Fixed in concourse 5.2.8.
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Concourse Open Redirect in the /sky/login endpoint
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
- Record
CVE-2020-5409- CVSS 3.0
- 7.6 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H - Weakness
- CWE-601
- Updated
- 2026-11-02
EUVDEUVD-2020-26583
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
- Record
EUVD-2020-26583- CVSS 3.0
- 7.6 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H - Updated
- 2026-11-03
NVD
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
- Record
CVE-2020-5409- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 3.0
- 7.6 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H - CVSS 2.0
- 5.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
OSV
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
- Record
CVE-2020-5409- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVBIT-concourse-2020-5409 No score
Concourse Open Redirect in the /sky/login endpoint
Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that user's access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
- Record
BIT-concourse-2020-5409- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
concourseBitnami |
before 5.2.8, 5.3.0 up to 5.5.10, 5.6.0 up to 5.8.1 | 5.2.85.5.105.8.1 |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-03 | aliases, published | EUVD |
| 2026-11-02 | created | CVE List, NVD, OSV |