Denial of Service (DoS) in SAPUI5 framework (Markdown-it component)

published 2025-12-09 11mo ago modified 2026-10-07 last mo. also EUVD-2025-201854

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

SAPUI5 (and OpenUI5) packages use outdated 3rd party libraries with known security vulnerabilities. When markdown-it encounters special malformed input, it fails to terminate properly, resulting in an infinite loop. This Denial of Service via infinite loop causes high CPU usage and system unresponsiveness due to a blocked processing thread. This vulnerability has no impact on confidentiality or integrity but has a high impact on system availability.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 11mo ago (2025-12-09)

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

SAP_SE SAPUI5 framework (Markdown-it component)

Classification

Weakness

CWE-405 Asymmetric Resource Consumption (Amplification)

References

Sources

CVE List CVE-2025-42873
NVD CVE-2025-42873

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