Evidence used
- CISA confirms exploitation in the wild.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 76.60% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2020
CVE-2020-13965High confidence
Roundcube Webmail Cross-Site Scripting (XSS) Vulnerability
roundcube · webmail
6.1MediumCVSS 3.1
Patch now
Patch availableCISA confirms exploitation in the wild and lists 2024-07-17 as the remediation due date.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Critical, raised 2 bands.upgradedsince 26 Jun 2024
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 roundcube webmail 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 | roundcube | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.4.5+dfsg.1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian bookwormbookworm · source | roundcube | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.4.5+dfsg.1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian forkyforky · source | roundcube | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.4.5+dfsg.1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian sidsid · source | roundcube | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.4.5+dfsg.1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
CISA confirms exploitation in the wild and lists 2024-07-17 as the remediation due date.
Patch available01
What, why and how
Roundcube Webmail contains a cross-site scripting (XSS) vulnerability that allows a remote attacker to manipulate data via a malicious XML attachment.
What
Roundcube Webmail contains a cross-site scripting (XSS) vulnerability that allows a remote attacker to manipulate data via a malicious XML attachment.
Why
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as <, >, and & that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
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
Roundcube Webmail contains a cross-site scripting (XSS) vulnerability that allows a remote attacker to manipulate data via a malicious XML attachment.
Why
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as <, >, and & that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
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 Confirmed in the wild
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2024-06-26.
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 → Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) → 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
- Changed: exploitation can affect a different security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-80 ↗
CWE-80: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as <, >, and & that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
- 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:C/C:L/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.SChangedScope: The attack can affect a component governed by a different security authority.CLowConfidentiality impact: A successful attack can cause a limited loss.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
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
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
- n/a: n/a
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- 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 9 Jun 2020 · Last source change 21 Oct 2025, 23:35 UTC · CWE-80 · Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
CVE recordCVE.org · 5.1
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-2020-6139
Product sourceCISA ADP
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Affected versionsThe structured affected or fixed version information changed.CISA ADP ↗
- Before
- n/a: n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
- After
- webmail: < 1.3.12, 1.4.0 < 1.4.5 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
- After
- n/a: n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
CVE published
Added to CISA KEV
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.