CVE-2020-5409
Concourse Open Redirect in the /sky/login endpoint
No known exploitation. EPSS puts it in the 60th percentile. Fixed versions are out.
No public exploit knownFix1 product4 fixed builds listed below
No ready-made check. Neither Nuclei nor OpenVAS has one for this CVE yet.
What to do
Find your product and version, then upgrade to the build on the right.
- Pivotal ConcourseAffected: ≥ unspecified, < 5.2.8Upgrade to: 5.2.8Affected: ≥ unspecified, < 5.5.10Upgrade to: 5.5.10Affected: ≥ unspecified, < 5.8.1Upgrade to: 5.8.1Affected: ≥ unspecified, < 6.0.0Upgrade to: 6.0.0Stated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
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.)
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.9% chance of exploitation activity in the next 30 days, which ranks it in the 60th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1653 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Scored 6.1 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1566Phishingmedium confidence
Sources
References in the record
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