CVE-2026-117533: REDAXO 5.18.0 before 5.21.4 Stored XSS via Unsanitized Mediapool SVG Uploads
Noroxi assessment
Priority: Monitor (action score 8/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.12% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. Special conditions such as timing or configuration are required.
- Fixed version: redaxo core 5.21.4.
Low priority for now. Upgrade to redaxo core 5.21.4 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
REDAXO from 5.18.0 before 5.21.4 contains a stored cross-site scripting vulnerability because rex_media_service moves uploaded SVG files into the public media folder before sanitizing them. Authenticated users with mediapool upload rights can race the sanitizer or exhaust memory limits to leave script-laden SVGs publicly served, executing scripts in victims' backend sessions.
- Published
- Oct 27, 2026
- Updated
- Oct 27, 2026
- EPSS
- 0.1% · 2th percentile
- CWE
- CWE-79
Report tools
Action score
8
Low priority for now.
- CVSS
- 8 / 40 · 2.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulnCheck
- 2.1
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Limit the impact of XSSCheck security headers
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Limit the impact of XSS
This is a cross-site scripting (XSS) vulnerability. A well-configured Content-Security-Policy doesn't fix it, but greatly reduces its impact. Check your site's CSP and other security headers for free.
Check security headersVersions reported by the vendor
Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.
redaxo core
- 5.21.4not affected
- 5.18.0 and later · before 5.21.4affected · semver
Same product
redaxo: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-117532REDAXO Core 5.3.0 before 5.21.4 Authentication Bypass via History Plugin37Monitor
- CVE-2026-117536REDAXO before 5.21.3 CSRF Token Bypass via users/users Privilege Escalation34Monitor
- CVE-2026-116896REDAXO before 5.21.5 Privilege Escalation via Backup Export of Authentication Tables30Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-116899Oct 27, 2026 · REDAXO before 5.21.4 Broken Access Control in Slice Operations28Monitor
- ← EarlierCVE-2026-116900Oct 27, 2026 · REDAXO before 5.21.4 Stored XSS via Media and Link Input Widgets20Monitor
- Later →CVE-2026-117534Oct 27, 2026 · REDAXO before 5.21.3 CSRF in Article History Plugin20Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| redaxo core | 5.21.4 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026+17 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- alham-rizvireporter
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-1169000 days apartREDAXO before 5.21.4 Stored XSS via Media and Link Input Widgets20Monitor
- CVE-2026-1175350 days apartREDAXO before 5.21.3 Reflected XSS via opener_link in Media Pool20Monitor
- CVE-2026-1175370 days apartREDAXO before 5.21.0 Reflected XSS via Metainfo API type Parameter8Monitor
- CVE-2026-1175380 days apartREDAXO before 5.21.0 Reflected XSS via Packages API function Parameter8Monitor
Not on record for this CVE: patch commit or PR link · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- P
- Scope
- X
Weakness class (CWE)
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')CVSS vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/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-secondary
Root cause
User content is inserted into the page as HTML. The browser interprets the content as code rather than data.
The bug in code
The whole CWE-79 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
commentEl.innerHTML = comment.body;Fixed
commentEl.textContent = comment.body;Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
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Change log
- SSVC exploitation— → none
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.