Low token entropy in MegaBIP

published 2025-05-23 last yr. modified 2026-06-17 4mo ago also EUVD-2025-27942

cvss: 9.1; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits: 0; none known

Token used for resetting passwords in MegaBIP software are generated using a small space of random values combined with a queryable value. It allows an unauthenticated attacker who know user login names to brute force these tokens and change account passwords (including these belonging to administrators). Version 5.20 of MegaBIP fixes this issue.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: last yr. (2025-05-23)

Exploit prediction

0.51% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.1	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	9.1	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

Jan Syski MegaBIP

Classification

Weakness

CWE-334 Small Space of Random Values

References

megabip.pl /index.php?id=24,145
vendor-advisory
cert.pl /en/posts/2025/05/CVE-2025-3893
third-party-advisory
gov.pl /web/cyfryzacja/rekomendacja-pelnomocnika-rzadu-ds-cyberbezpieczenstwa-dotyczaca-biuletynow-informacji-publicz
government-resource

Sources

CVE List CVE-2025-3895
NVD CVE-2025-3895

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