How severe is CVE-2024-20392?

CVE-2024-20392 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2024-20392 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-20392?

CVE-2024-20392 primarily affects Cisco Asyncos. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-20392?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-20392 have an EU (EUVD) identifier?

Yes. CVE-2024-20392 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18107.

When was CVE-2024-20392 published?

CVE-2024-20392 was published on 2024-05-15 and last updated on 2026-06-17.

CVE-2024-20392

CVE-2024-20392 is a medium-severity vulnerability in Cisco Asyncos with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-113.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-18107
Weakness: CWE-113
Affected product: Cisco Asyncos
Published: 2024-05-15
Last modified: 2026-06-17

Description

A vulnerability in the web-based management API of Cisco AsyncOS Software for Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack. This vulnerability is due to insufficient input validation of some parameters that are passed to the web-based management API of the affected system. An attacker could exploit this vulnerability by persuading a user of an affected interface to click a crafted link. A successful exploit could allow the attacker to perform cross-site scripting (XSS) attacks, resulting in the execution of arbitrary script code in the browser of the targeted user, or could allow the attacker to access sensitive, browser-based information.

Frequently asked questions

What is CVE-2024-20392?: A vulnerability in the web-based management API of Cisco AsyncOS Software for Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack. This vulnerability is due to insufficient input validation of some parameters that are passed to the web-based management API of the affected system. An attacker could exploit this vulnerability by persuading a user of an affected interface to click a crafted link. A successful exploit could allow the attacker to perform cross-site scripting (XSS) attacks, resulting in the execution of arbitrary script code in the browser of the targeted user, or could allow the attacker to access sensitive, browser-based information.
How severe is CVE-2024-20392?: CVE-2024-20392 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2024-20392 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-20392?: CVE-2024-20392 primarily affects Cisco Asyncos. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-20392?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-20392 have an EU (EUVD) identifier?: Yes. CVE-2024-20392 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18107.
When was CVE-2024-20392 published?: CVE-2024-20392 was published on 2024-05-15 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-http-split-GLrnnOwS

Affected products (21)

cpe:2.3:o:cisco:asyncos:11.0.3-238:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:11.1.0-069:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:11.1.0-128:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.0.0-419:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.1.0-071:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.1.0-087:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.1.0-089:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.5.0-066:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.5.3-041:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:12.5.4-041:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:13.0.0-392:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:13.0.5-007:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:13.5.1-277:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:13.5.4-038:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:14.0.0-698:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:14.2.0-620:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:14.2.1-020:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:14.3.0-032:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:15.0.0-104:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:15.0.1-030:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asyncos:15.5.0-048:*:*:*:*:*:*:*

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