CVE-2020-26280: OpenSlides is a free, Web-based presentation and assembly system for managing and projecting agenda, motions, and elections of assemblies.
Noroxi assessment
Priority: Monitor (action score 35/100)
- 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: 1.3% (FIRST EPSS); higher than 71.8% of all records.
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
- Fixed version: OpenSlides OpenSlides 3.3.
Low priority for now. Upgrade to OpenSlides OpenSlides 3.3 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
OpenSlides is a free, Web-based presentation and assembly system for managing and projecting agenda, motions, and elections of assemblies. OpenSlides version 3.2, due to unsufficient user input validation and escaping, it is vulnerable to persistant cross-site scripting (XSS). In the web applications users can enter rich text in various places, e.g. for personal notes or in motions. These fields can be used to store arbitrary JavaScript Code that will be executed when other users read the respective text. An attacker could utilize this vulnerability be used to manipulate votes of other users, hijack the moderators session or simply disturb the meeting. The vulnerability was introduced with 6eae497abeab234418dfbd9d299e831eff86ed45 on 16.04.2020, which is first included in the 3.2 release. It has been patched in version 3.3 ( in commit f3809fc8a97ee305d721662a75f788f9e9d21938, merged in master on 20.11.2020).
- Published
- Dec 18, 2020
- Updated
- Jun 16, 2026
- EPSS
- 1.3% · 71th percentile
- CWE
- CWE-79
Report tools
Action score
35
Monitor
Low priority for now.
- CVSS
- 35 / 40 · 8.9 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.3%
CNA vs NVD score
- NVD
- 8.9
- CNA · GitHub_M
- 8.9
- agree
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.
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Noroxi 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.
| Vendor | Product | CPE |
|---|---|---|
| openslides | openslides | cpe:2.3:a:openslides:openslides |
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 headersAffected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- openslides openslides3.2
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
OpenSlides OpenSlides
- = 3.2affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| PyPI | openslides | before 3.3 | 3.3 |
Same product
openslides: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-25519OpenSlides has incorrect access control vulnerability in authentication service39Monitor
- CVE-2024-22893OpenSlides 4.0.15 verifies passwords by comparing password hashes using a function with content-dependent runtime.30Monitor
- CVE-2024-22892OpenSlides 4.0.15 was discovered to be using a weak hashing algorithm to store passwords.30Monitor
Published before and after this one in the same product
- Later →CVE-2025-30342Mar 21, 2025 · An XSS issue was discovered in OpenSlides before 4.2.5.24Monitor
- Later →CVE-2025-30343Mar 21, 2025 · A directory traversal issue was discovered in OpenSlides before 4.2.5.26Monitor
- Later →CVE-2025-30344Mar 21, 2025 · An issue was discovered in OpenSlides before 4.2.5.14Monitor
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 |
|---|---|---|
| OpenSlides OpenSlides | 3.3 · description | Vendor (CNA) |
| PyPI:openslides | 3.3 | Package registry (OSV) |
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.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- low · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- Low
Weakness class (CWE)
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L
nvd-primary
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
—
Change log
- Fix✗ → ✓
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References
Show all references (4 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.