CVE-2024-21654 | rubygems.org MFA Bypass through password reset function could allow account takeover

Rubygems.org is the Ruby community's gem hosting service. Rubygems.org users with MFA enabled would normally be protected from account takeover in the case of email account takeover. However, a workaround on the forgotten password form allows an attacker to bypass the MFA requirement and takeover the account. This vulnerability has been patched in commit 0b3272a.

Published: 2024-01-12 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-21654 is rated Low Risk (32.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.48%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-21654

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.13% 0.48% +0.35%
2 2025-12-29 0.16% 0.13% -0.03%
3 2025-12-04 — 0.16% —

Full EPSS history (23 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-21654

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 2.5 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2024-21654

OS Trackers for CVE-2024-21654

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2024-21654

Affected software / configurations for CVE-2024-21654

Vendor Product Version Raw CPE
rubygems rubygems.org < 2024-01-08 cpe:2.3:a:rubygems:rubygems.org:*:*:*:*:*:*:*:*

References for CVE-2024-21654

cvelogic Threat Intelligence