Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.21% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-100720High confidence
Froxlor before 2.3.12 Stored XSS via SSL certificate issuer
froxlor · froxlor
Official source article: GitHub GHSA-89VJ-GQQR-73P8 ↗. Check the applicable product and release in the original source.
9.3CriticalCVSS 4.0
Within 7 days
Patch availableCritical technical severity; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs froxlor froxlor 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.
Critical technical severity; prioritise exposed affected systems while verifying vendor guidance.
Patch available01
What, why and how
Froxlor 2.0.0 through 2.3.10 is vulnerable to stored cross-site scripting. When a customer (the lowest-privileged authenticated role) uploads an SSL certificate for one of their own domains, the Certificates API add()/update() methods parse it with openssl_x509_parse() and store the issuer organization (issuer['O']) value verbatim without sanitization. Froxlor's table-listing renderer then emits scalar cells through Twig's `raw` filter, disabling HTML auto-escaping, so when an administrator or reseller opens Domains > SSL certificates the attacker-supplied issuer value executes as script in the privileged user's session. This crosses a privilege boundary from customer to admin and can result in full administrator account takeover; because a Froxlor admin controls webserver, DNS, and PHP configuration applied by a cron job running as root, the issue can be further escalated to command execution as root on the managed server. The issue is fixed in Froxlor 2.3.12.
What
Froxlor 2.0.0 through 2.3.10 is vulnerable to stored cross-site scripting. When a customer (the lowest-privileged authenticated role) uploads an SSL certificate for one of their own domains, the Certificates API add()/update() methods parse it with openssl_x509_parse() and store the issuer organization (issuer['O']) value verbatim without sanitization. Froxlor's table-listing renderer then emits scalar cells through Twig's `raw` filter, disabling HTML auto-escaping, so when an administrator or reseller opens Domains > SSL certificates the attacker-supplied issuer value executes as script in the privileged user's session. This crosses a privilege boundary from customer to admin and can result in full administrator account takeover; because a Froxlor admin controls webserver, DNS, and PHP configuration applied by a cron job running as root, the issue can be further escalated to command execution as root on the managed server. The issue is fixed in Froxlor 2.3.12.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may bypass an access boundary or take over an account.
What
Froxlor 2.0.0 through 2.3.10 is vulnerable to stored cross-site scripting. When a customer (the lowest-privileged authenticated role) uploads an SSL certificate for one of their own domains, the Certificates API add()/update() methods parse it with openssl_x509_parse() and store the issuer organization (issuer['O']) value verbatim without sanitization. Froxlor's table-listing renderer then emits scalar cells through Twig's `raw` filter, disabling HTML auto-escaping, so when an administrator or reseller opens Domains > SSL certificates the attacker-supplied issuer value executes as script in the privileged user's session. This crosses a privilege boundary from customer to admin and can result in full administrator account takeover; because a Froxlor admin controls webserver, DNS, and PHP configuration applied by a cron job running as root, the issue can be further escalated to command execution as root on the managed server. The issue is fixed in Froxlor 2.3.12.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may bypass an access boundary or take over an account.
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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') → bypass an access boundary or take over an account
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- Passive interaction required
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Not a CVSS 4.0 base metric
- 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:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:NCommon Vulnerability Scoring System 4.0: 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.ATNoneAttack requirements: No additional deployment or execution condition is required.PRLowPrivileges required: The attacker needs basic user-level privileges.UIPassiveUser interaction: A user must unknowingly interact with the vulnerable system.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VANoneVulnerable-system availability: No direct loss is represented by this metric.SCHighSubsequent-system confidentiality: A successful attack can cause a major loss.SIHighSubsequent-system integrity: A successful attack can cause a major loss.SANoneSubsequent-system availability: 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
- Froxlor: 2.0.0 < 2.3.12
- Fixed
- froxlor: 2.3.12
- 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 26 Sept 2026 · Last source change 26 Sept 2026, 23:02 UTC · CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-09-27
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-87693
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- ENISA EUVD mappingEUVD-2026-87693 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-87693"}
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
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.