Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 8.25% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2024
CVE-2024-31204High confidence
mailcow Cross-site Scripting Vulnerability via Exception Handler
mailcow · mailcow-dockerized
Official source article: GitHub GHSA-FP6H-63W4-5HCM ↗. Check the applicable product and release in the original source.
6.1MediumCVSS 3.1
Within 7 days
Fix not verifiedMedium 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:Medium, unchanged from published severity.unchanged
Compensating controls
- Restrict local access and enforce least privilege on affected hosts.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs mailcow mailcow-dockerized and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Fix not verified01
What, why and how
mailcow: dockerized is an open source groupware/email suite based on docker. A security vulnerability has been identified in mailcow affecting versions prior to 2024-04. This vulnerability resides in the exception handling mechanism, specifically when not operating in DEV_MODE. The system saves exception details into a session array without proper sanitization or encoding. These details are later rendered into HTML and executed in a JavaScript block within the user's browser, without adequate escaping of HTML entities. This flaw allows for Cross-Site Scripting (XSS) attacks, where attackers can inject malicious scripts into the admin panel by triggering exceptions with controlled input. The exploitation method involves using any function that might throw an exception with user-controllable argument. This issue can lead to session hijacking and unauthorized administrative actions, posing a significant security risk. Version 2024-04 contains a fix for the issue.
What
mailcow: dockerized is an open source groupware/email suite based on docker. A security vulnerability has been identified in mailcow affecting versions prior to 2024-04. This vulnerability resides in the exception handling mechanism, specifically when not operating in DEV_MODE. The system saves exception details into a session array without proper sanitization or encoding. These details are later rendered into HTML and executed in a JavaScript block within the user's browser, without adequate escaping of HTML entities. This flaw allows for Cross-Site Scripting (XSS) attacks, where attackers can inject malicious scripts into the admin panel by triggering exceptions with controlled input. The exploitation method involves using any function that might throw an exception with user-controllable argument. This issue can lead to session hijacking and unauthorized administrative actions, posing a significant security risk. Version 2024-04 contains a fix for the issue.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through an adjacent network may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
mailcow: dockerized is an open source groupware/email suite based on docker. A security vulnerability has been identified in mailcow affecting versions prior to 2024-04. This vulnerability resides in the exception handling mechanism, specifically when not operating in DEV_MODE. The system saves exception details into a session array without proper sanitization or encoding. These details are later rendered into HTML and executed in a JavaScript block within the user's browser, without adequate escaping of HTML entities. This flaw allows for Cross-Site Scripting (XSS) attacks, where attackers can inject malicious scripts into the admin panel by triggering exceptions with controlled input. The exploitation method involves using any function that might throw an exception with user-controllable argument. This issue can lead to session hijacking and unauthorized administrative actions, posing a significant security risk. Version 2024-04 contains a fix for the issue.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through an adjacent network may attempt exploitation with low privileges. 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
- an adjacent network → Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Adjacent
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- Required interaction required
- Attack complexity
- High: exploitation depends on specific conditions
- 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-79 ↗
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'). The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:A/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major 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. - Fix not verified
- Affected
- mailcow-dockerized: < 2024-04
- Fixed
- No fixed version is explicitly recorded in the structured CVE data.
- Action
- No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 4 Apr 2024 · Last source change 12 Dec 2024, 20:53 UTC · CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE recordCVE.org · 5.1
CVSS sourceCNA
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-2024-29108
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
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
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
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.