CVE-2026-21850 (CVSS 6.5)

Description

HCL AION is affected by a vulnerability where user-controlled input could be included in HTTP response headers without proper neutralization of CR/LF characters. This may allow an attacker to inject headers or split responses, potentially resulting in unintended behavior or security impact under certain conditions.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.12%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-113 CWE-113

References

Other References

https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0135118

Frequently Asked Questions

What is CVE-2026-21850? +

HCL AION is affected by a vulnerability where user-controlled input could be included in HTTP response headers without proper neutralization of CR/LF characters. This may allow an attacker to inject headers or split responses, potentially resulting in unintended behavior or security impact under certain conditions. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-21850? +

CVE-2026-21850 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0022, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-21850? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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