CVE-2023-26303
LOWDescription
Denial of service could be caused to markdown-it-py, before v2.2.0, if an attacker was allowed to force null assertions with specially crafted input.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Exploit Intelligence
Low risk: more likely to be exploited than 14% of all known CVEs.
References
Related Vulnerabilities
Other CWE-173 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2026-10050 | Critical | 9.1 | 0.5% | - | Fix |
| CVE-2026-19611 | High | 7.4 | 0.3% | - | - |
| CVE-2024-54158 | Low | 3.5 | 0.3% | - | Fix |
| CVE-2023-26302 | Low | 3.3 | 0.2% | - | Fix |
| CVE-2026-81638 | Low | 2.1 | 0.1% | - | - |
Common questions
How do I fix CVE-2023-26303?
Upgrade markdown-it-py on debian 12 to 2.1.0-5 or later.
Is CVE-2023-26303 being actively exploited?
Not that we know of. CVE-2023-26303 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.23% is the estimated probability that it will be exploited in the next 30 days. That is higher than 14% of all scored CVEs.
How severe is CVE-2023-26303?
CVE-2023-26303 has a CVSS v3 base score of 3.3, rated low. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2023-26303 affect?
Published advisories record a fix for markdown-it-py (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2023-26303
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-17.