CVE-2020-4640

Certain IBM API Connect 10.0.0.0 through 10.0.1.0 and 2018.4.1.0 through 2018.4.1.13 configurations can result in sensitive information in the URL fragment identifiers. This information can be cached in the intermediate nodes like proxy servers, cdn, logging platforms, etc. An attacker can make use of this information to perform attacks by impersonating a user. IBM X-Force ID: 185510.

Published: 2021-02-04 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-4640 is rated Low Risk (25.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.35%). 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-2020-4640

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 0.08% 0.35% +0.27%
2 2025-03-17 0.04% 0.08% +0.03%
3 2023-03-07 — 0.04% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4640

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.1 3.1 MEDIUM
CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N 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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.
 1.5 2.5 [email protected]
3.4 3.0 LOW
CVSS:3.0/AV:A/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.
 0.9 2.5 [email protected]
3.8 2.0 LOW
AV:A/AC:M/Au:S/C:P/I:P/A:N Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 4.4 4.9 [email protected]

Weakness enumeration for CVE-2020-4640

Affected software / configurations for CVE-2020-4640

Vendor Product Version Raw CPE
ibm api_connect >= 2018.4.1.0, <= 2018.4.1.13 cpe:2.3:a:ibm:api_connect:*:*:*:*:*:*:*:*
ibm api_connect 10.0.0.0 cpe:2.3:a:ibm:api_connect:10.0.0.0:*:*:*:*:*:*:*
ibm api_connect 10.0.1.0 cpe:2.3:a:ibm:api_connect:10.0.1.0:*:*:*:*:*:*:*

References for CVE-2020-4640

cvelogic Threat Intelligence