Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 1.67% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2020
CVE-2020-8166High confidence
n/a https://github.com/rails/rails — Cross-Site Request Forgery (CSRF)
Unknown · https://github.com/rails/rails
4.3MediumCVSS 3.1
Within 7 days
Patch availableMedium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:High, raised one band.upgradedsince 28 Apr 2026
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs Unknown https://github.com/rails/rails and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Distribution package intelligence
4 package statesRelease-specific package status
Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Debian trixietrixie · source | rails | Vendor fix publishedDebian records a fixed source-package version for this release. | 2:5.2.4.3+dfsg-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian bookwormbookworm · source | rails | Vendor fix publishedDebian records a fixed source-package version for this release. | 2:5.2.4.3+dfsg-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian forkyforky · source | rails | Vendor fix publishedDebian records a fixed source-package version for this release. | 2:5.2.4.3+dfsg-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian sidsid · source | rails | Vendor fix publishedDebian records a fixed source-package version for this release. | 2:5.2.4.3+dfsg-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
Open-source package ranges4 source-attributed ranges
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
| Ecosystem and package | Affected range | First fixed version | Evidence |
|---|---|---|---|
| RubyGemsactionpack | ECOSYSTEM: introduced 5.0.0; fixed 5.2.4.3 | 5.2.4.3 | OSV record ↗aggregator derived · 5 May 2026 |
| RubyGemsactionpack | ECOSYSTEM: introduced 6.0.0; fixed 6.0.3.1 | 6.0.3.1 | OSV record ↗aggregator derived · 5 May 2026 |
| rubygemsactionpack | >= 5.0.0, <= 5.2.4.2 | 5.2.4.3 | GitHub advisory ↗github reviewed aggregator · 5 May 2026 |
| rubygemsactionpack | >= 6.0.0, <= 6.0.3 | 6.0.3.1 | GitHub advisory ↗github reviewed aggregator · 5 May 2026 |
Direct vendor intelligence
1 currentAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
CVE-2020-8166 · CSAF 2.0 · revision 43 · interimSUSE Product Security TeamCVE-2020-8166
The vendor explicitly identifies these products as affected by this CVE.
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP1
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP1
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP2
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP2
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP3
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP3
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP4
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP4
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP5
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP5
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP6
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP6
- Summary
- A CSRF forgery vulnerability exists in rails < 5.2.5, rails < 6.0.4 that makes it possible for an attacker to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token.
- Remediation
- To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available01
What, why and how
A CSRF forgery vulnerability exists in rails < 5.2.5, rails < 6.0.4 that makes it possible for an attacker to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token.
What
A CSRF forgery vulnerability exists in rails < 5.2.5, rails < 6.0.4 that makes it possible for an attacker to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token.
Why
The application accepts a state-changing browser request without a reliable anti-forgery check.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
A CSRF forgery vulnerability exists in rails < 5.2.5, rails < 6.0.4 that makes it possible for an attacker to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token.
Why
The application accepts a state-changing browser request without a reliable anti-forgery check.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material Reference recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
- Likely attack path
- a network path → Cross-Site Request Forgery (CSRF) → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- Required interaction required
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-352 ↗
CWE-352: Cross-Site Request Forgery (CSRF). The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Affected
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP1
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP1
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP2
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP2
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP3
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP3
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP4
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP4
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP5
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP5
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP6
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP6
- ruby2.5-rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP7
- rubygem-rails-5_1 as component of SUSE Linux Enterprise High Availability Extension 15 SP7
- SLES 15 SP1 CHOST Images for Amazon EC2
- SLES 15 SP2 CHOST Images for Amazon EC2
- SLES 15 SP3 CHOST Images for Amazon EC2
- SLES 15 SP4 CHOST Images for Amazon EC2
- SLES 15 SP5 CHOST Images for Amazon EC2
- SLES 15 SP1 CHOST Images for Google
- SLES 15 SP2 CHOST Images for Google
- SLES 15 SP3 CHOST Images for Google
- SLES 15 SP4 CHOST Images for Google
- SLES 15 SP5 CHOST Images for Google
- SLES 15 SP1 CHOST Images for Microsoft Azure
- SLES 15 SP2 CHOST Images for Microsoft Azure
- SLES 15 SP3 CHOST Images for Microsoft Azure
- SLES 15 SP4 CHOST Images for Microsoft Azure
- SLES 15 SP5 CHOST Images for Microsoft Azure
- ruby2.5-rubygem-rails-5_1 as component of openSUSE Leap 15.5
- and 5 more
- Action
- To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 2 Jul 2020 · Last source change 28 Apr 2026, 15:45 UTC · CWE-352 · Cross-Site Request Forgery (CSRF)
CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2020-0429
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD modified after enrichment
Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.