Chevereto before 3.17.1 allows Cross Site Scripting (XSS) via an image title at the image upload stage.

published 2021-06-30 5y ago modified 2026-07-09 4mo ago also EUVD-2021-18605

cvss: 6.1; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

Patch / fix

fixed in 1

chevereto chevereto 3.17.1

Is CVE-2021-31721 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

exploit-db.com https://www.exploit-db.com/exploits/49859 referenced PoC, tagged "exploit" by a source, unverified
packetstormsecurity.com http://packetstormsecurity.com/files/164183/Cloudron-6.2-Cross-Site-Scripting.html 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

exploit-db.com /exploits/49859
exploit, third-party-advisory, vdb-entry
packetstormsecurity.com /files/164183/Cloudron-6.2-Cross-Site-Scripting.html
exploit, third-party-advisory, vdb-entry

Sources

CVE List CVE-2021-31721
NVD CVE-2021-31721

Fencer Intel 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.