CVE-2021-41592

Blockstream c-lightning through 0.10.1 allows loss of funds because of dust HTLC exposure.

Published: 2021-10-04 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-41592 is rated Moderate Risk (63.5/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.83%). Mandatory action: Review affected assets and schedule remediation.

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-2021-41592

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 2025-05-23 0.63% 0.83% +0.20%
2 2025-03-30 1.32% 0.63% -0.69%
3 2025-03-29 1.32%

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-41592

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.4 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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:L)
Some sensitive info could get out, but not a total data dump.
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 5.5 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-41592

Affected software / configurations for CVE-2021-41592

Vendor Product Version Raw CPE
elementsproject c-lightning <= 0.10.1 cpe:2.3:a:elementsproject:c-lightning:*:*:*:*:*:*:*:*

References for CVE-2021-41592

cvelogic Threat Intelligence