CVE-2026-40587

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 58/100
Published: 2026-04-21 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: High
UI: None
S: Unchanged
C: High
I: High
A: None

Description

blueprintUE is a tool to help Unreal Engine developers. Prior to 4.2.0, when a user changes their password via the profile edit page, or when a password reset is completed via the reset link, neither operation invalidates existing authenticated sessions for that user. A server-side session store associates userID → session; the current password change/reset flow updates only the password column in the users table and does not destroy or mark invalid any active sessions. As a result, an attacker who has already compromised a session retains full access to the account indefinitely — even after the legitimate user has detected the intrusion and changed their password — until the session's natural expiry time (configured as SESSION_GC_MAXLIFETIME, defaulting to 86400 seconds / 24 hours, with SESSION_LIFETIME=0 meaning persistent until browser close or GC, whichever is later). This vulnerability is fixed in 4.2.0.

Weakness Classification (1)

Bug Bounty Relevance

58 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

6.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

EPSS — Exploitation Probability

0.24%
Raw Score 0.002420
Percentile 15.3%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00242
2026-10-28
0.00242

Intelligence Sources

nvd ref →