Pivotal Concourse Open Redirect in Login Flow

Description

Pivotal Concourse Release, versions 4.x prior to 4.2.2, login flow allows redirects to untrusted websites. 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.

Specific Go Packages Affected

github.com/concourse/concourse/skymarshal/skyserver

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Not specified
Published (advisory)
2022-02-15 01:57:18 UTC
Updated
2023-10-02 11:43:17 UTC
GitHub reviewed
2021-05-12 18:15:16 UTC

EPSS Score

Score Percentile
0.56% 67.53%

CVSS Scores

Base score Version Severity Vector
5.4 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

Affected packages (3)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go github.com/concourse/concourse < 5.2.8 5.2.8
go github.com/concourse/concourse >= 5.3.0, < 5.5.10 5.5.10
go github.com/concourse/concourse >= 5.6.0, < 5.8.1 5.8.1

References

cvelogic Threat Intelligence