CVE-2021-42564 json
An open redirect through HTML injection in confidential messages in Cryptshare before 5.1.0 allows remote attackers (with permission to pro…
published 2021-11-30 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-29532
- cvss
- 5.4
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 52%
- public exploits
- 0
- none known
Summary
An open redirect through HTML injection in confidential messages in Cryptshare before 5.1.0 allows remote attackers (with permission to provide confidential messages via Cryptshare) to redirect targeted victims to any URL via the '<meta http-equiv="refresh"' substring in the editor parameter.
Patch / fix
- cryptshare cryptshare_server 5.1.0
Exploit prediction
0.69% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- syss.de https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-057.txt referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| 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 | 4.9 | AV:N/AC:M/Au:S/C:P/I:P/A:N |
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
syss.de
/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-057.txt
exploit, third-party-advisory
Sources
- CVE List CVE-2021-42564
- NVD CVE-2021-42564
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.