CVE-2021-34817 json
A Cross-Site Scripting (XSS) issue in the chat component of Etherpad 1.8.13 allows remote attackers to inject arbitrary JavaScript or HTML…
published 2021-07-19 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21464
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 71%
- public exploits
- 0
- none known
Summary
A Cross-Site Scripting (XSS) issue in the chat component of Etherpad 1.8.13 allows remote attackers to inject arbitrary JavaScript or HTML by importing a crafted pad.
Patch / fix
Exploit prediction
1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/ether/etherpad-lite/commit/a7968115581e20ef47a533e030f59f830486bdfa referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/ether/etherpad-lite/commit/a7968115581e20ef47a533e030f59f830486bdfa
exploit, patch, third-party-advisory
-
etherpad.org
/#download
patch, vendor-advisory
-
github.com
/ether/etherpad-lite/releases/tag/1.8.14
patch, release-notes, third-party-advisory
-
blog.sonarsource.com
/etherpad-code-execution-vulnerabilities
third-party-advisory
Sources
- CVE List CVE-2021-34817
- NVD CVE-2021-34817
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.