CVE-2022-21650 json
Stored XSS via html file upload in convos
published 2022-01-04 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-26871
- cvss
- 7.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
Summary
Convos is an open source multi-user chat that runs in a web browser. You can't use SVG extension in Convos' chat window, but you can upload a file with an .html extension. By uploading an SVG file with an html extension the upload filter can be bypassed. This causes Stored XSS. Also, after uploading a file the XSS attack is triggered upon a user viewing the file. Through this vulnerability, an attacker is capable to execute malicious scripts. Users are advised to update as soon as possible.
Patch / fix
- convos convos 6.52
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 18 mo ago
Exploit prediction
0.86% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- huntr.dev https://www.huntr.dev/bounties/ae424798-de01-4972-b73b-2db674f82368/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N |
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
Affected products
- convos-chat convos
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/convos-chat/convos/commit/5c0a1ec9a2c147bc3b63fd5a48da5f32e18fe5df
patch, third-party-advisory
-
huntr.dev
/bounties/ae424798-de01-4972-b73b-2db674f82368/
exploit, issue-tracking, patch, third-party-advisory
-
github.com
/convos-chat/convos/security/advisories/GHSA-mm2v-4v7g-m695
patch, third-party-advisory
-
blog.pocas.kr
/2021/12/30/2021-12-30-s-xss-convos-chat/#First-vulnerability
broken-link
Sources
- CVE List CVE-2022-21650
- NVD CVE-2022-21650
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.