CVE-2020-36661 | Kong lua-multipart multipart.lua is_header redos

A vulnerability was found in Kong lua-multipart 0.5.8-1. It has been declared as problematic. This vulnerability affects the function is_header of the file src/multipart.lua. The manipulation leads to inefficient regular expression complexity. Upgrading to version 0.5.9-1 is able to address this issue. The patch is identified as d632e5df43a2928fd537784a99a79dec288bf01b. It is recommended to upgrade the affected component. VDB-220642 is the identifier assigned to this vulnerability.

Published: 2023-02-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-36661 is rated Low Risk (36.3/100): CVSS Low severity, with medium exploitation likelihood (EPSS 0.46%). Mandatory action: 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-2020-36661

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 2026-02-25 0.44% 0.46% +0.01%
2 2026-02-15 0.28% 0.44% +0.17%
3 2026-02-14 0.28%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-36661

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.5 3.1 LOW
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:L)
A normal user session is enough; they don’t have to be admin.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
2.1 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
2.7 2.0 LOW
AV:A/AC:L/Au:S/C:N/I:N/A:P Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
5.1 2.9 [email protected]

Weakness enumeration for CVE-2020-36661

Affected software / configurations for CVE-2020-36661

Vendor Product Version Raw CPE
konghq multipart 0.5.8-1 cpe:2.3:a:konghq:multipart:0.5.8-1:*:*:*:*:lua:*:*

References for CVE-2020-36661

cvelogic Threat Intelligence