CVE-2021-38997: ibm api_connect
Vulnerability summary
CVE-2021-38997 is a medium (CVSS 5.4) vulnerability in ibm api_connect. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 33.5% of scored vulnerabilities.
Timeline
- 01-12-2022PublishedVulnerability first disclosed.
- 23-04-2025Last modifiedVulnerability information updated.
Description
IBM API Connect V10.0.0.0 through V10.0.5.0, V10.0.1.0 through V10.0.1.7, and V2018.4.1.0 through 2018.4.1.19 is vulnerable to HTTP header injection, caused by improper validation of input by the HOST headers. This could allow an attacker to conduct various attacks against the vulnerable system, including cross-site scripting, cache poisoning or session hijacking. IBM X-Force ID: 213212.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.41%
Chance of exploitation in the next 30 days
Percentile
34%
Versus all other CVEs
30-day change
+0.01 pp
From 0.39% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-644Improper Neutralization of HTTP Headers for Scripting SyntaxThe product does not neutralize or incorrectly neutralizes web scripting syntax in HTTP headers that can be used by web browser components that can process raw headers, such as Flash.
- CWE-116Improper Encoding or Escaping of OutputThe product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
Affected systems
Ibm1 product
- api_connect≥ 10.0.0.0, < 10.0.5.0 | ≥ 10.0.1.0, < 10.0.1.7 | ≥ 2018.4.1.0, < 2018.4.1.19 | ≥ 10.0.0.0, ≤ 10.0.5.0 | ≥ 10.0.1.0, ≤ 10.0.1.7 | ≥ 2018.4.1.0, ≤ 2018.4.1.19
1 vendor · 1 product