In WoWonder 3.0.4, remote attackers can take over any account due to the weak cryptographic algorithm in recover.php.

published 2021-06-11 5y ago modified 2026-06-17 4mo ago also EUVD-2021-13965

cvss: 9.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 3.4%; EPSS 3.4% chance of exploitation in 30 days, percentile 88%
public exploits: 0; none known

In WoWonder 3.0.4, remote attackers can take over any account due to the weak cryptographic algorithm in recover.php. The code parameter is easily predicted from the time of day.

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Exploit prediction

3.36% chance of exploitation in the next 30 days, higher than 88% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

securityforeveryone.com https://securityforeveryone.com/blog/wowonder-0-day-vulnerability-cve-2021-27200 referenced PoC, tagged "exploit" by a source, unverified
exploit-db.com https://www.exploit-db.com/exploits/49989 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

CWE-330 Use of Insufficiently Random Values

References

securityforeveryone.com /blog/wowonder-0-day-vulnerability-cve-2021-27200
exploit, third-party-advisory
exploit-db.com /exploits/49989
exploit, third-party-advisory, vdb-entry
wowonder.com
product

Sources

CVE List CVE-2021-27200
NVD CVE-2021-27200

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