CVE-2017-20290

Discourse < 1.9.0.beta13 Reflected XSS via /email/unsubscribed

CVSS score

5.1

EPSS probability

—

Risk score

0.5

Published

3 h ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

Impact on My Inventory

Only the personal products you have added to your account are assessed; an organisation's inventory does not appear here.

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Vulnerability description

DayBreach AI Explanation

Verified against sources

CVE-2017-20290: Discourse /email/unsubscribed Reflected XSS Vulnerability

Sources read

Source agreement

0/2

Evidence confidence

%47

Short explanation

Discourse contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, executing JavaScript in victims' browsers.

Why does it matter?

This unauthenticated vulnerability allows attackers to execute JavaScript in users' browsers via specially crafted links. Sources present a conflict regarding the CVSS base score, and patch status is assessed as available in the supplied evidence.

What should be done?

Follow vendor advisories and patch commits
Upgrade Discourse software to fixed versions

Note on uncertainty

2 alanda kaynak uyuşmazlığı var. DayBreach bu değerleri saklamadı; kaynak karşılaştırması aşağıda gösteriliyor.

Chain of evidence and sources3 verified claims

Discourse uygulamasinin 1.9.0.beta2 ile 1.9.0.beta13 surumleri arasinda yansitilmis XSS açigi bulunmaktadir.

S0 · daybreach-canonical S1 · cvelist S2 · nvd

Saldirganlar email parametresi uzerinden SVG onload yukleri iceren GET istekleri olusturabilir.

S0 · daybreach-canonical S1 · cvelist S2 · nvd

Kaynaklar arasinda CVSS taban puani konusunda 5.1 ile 6.1 arasinda farkliliklar bulunmaktadir.

S0 · daybreach-canonical S1 · cvelist S2 · nvd

Show the technical text from the sources

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb renders unescaped via html_safe, executing JavaScript in victims' browsers. Exploitation evidence was first observed by the Shadowserver Foundation on 2023-10-19.

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CWE: CWE-79

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2017-20290 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	discourse	discourse	View

Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
6.1	CVSS V3_1	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N	CVE CNA
6.1	CVSS V31	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N	NVD
5.1	CVSS V4_0	MEDIUM	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N	CVE CNA
5.1	CVSS V40	MEDIUM	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

4 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

cvelist

Fix Commit

Open source

cvelist

Introducing Commit

Open source

reference

Fix Commit

Open source

reference

Introducing Commit

Open source

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Apply the official update named in the evidence only to the matching product and version.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2017-20290 is associated with the following CWEs:

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2017-20290 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden

PermissionsGerekmiyor

User—

Official Sources and Advisories

Fix Commitpatch Introducing Commitpatch Nuclei Templatevendor-advisory VulnCheck Advisory: Discourse < 1.9.0.beta13 Reflected XSS via /email/unsubscribedvendor-advisory

CVSS Vector Radar Chart

5.1 / 10

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone required

User InteractionA

Confidentiality (Gizlilik)Low

Integrity (Bütünlük)A

Availability (Erişilebilirlik)None

Yama doğrulandı

4 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

Follow the vendor

discourse

Weakness Type (CWE & CAPEC)

CWE-79

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Get this vulnerability through the API

Affected products, version ranges, exploitation status and patch information in a single request, with a free key.

Get a free key Documentation

curl -H "x-api-key: $DAYBREACH_API_KEY" \
  "https://api.daybreach.dev/api/v1/intel/cves/CVE-2017-20290"

Discourse < 1.9.0.beta13 Reflected XSS via /email/unsubscribed

Impact on My Inventory

Vulnerability description

DayBreach AI Explanation

Short explanation

What should be done?

IMPACT: Affected Products and Software

Affected Products

RED HAT CSAF/VEX: Product Impact Check

SCORING: CVSS from Multiple Sources

CVSS Scores

Patch and Remediation Guide

Solution & Remediation Advisory

Public exploit and active exploitation status

Verified exploit intelligence

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

Common Attack Pattern Enumeration and Classification (CAPEC)

Attack Vector and Accessibility

Official Sources and Advisories

CVSS Vector Radar Chart

Vulnerability Scoring Details

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

Get this vulnerability through the API

DayBreach

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