How severe is CVE-2019-25102?

CVE-2019-25102 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-25102?

CVE-2019-25102 affects the following packages: simple-markdown (npm). Ecosystems affected: npm.

How do I fix CVE-2019-25102?

Update simple-markdown to 0.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-25102 is resolved across your whole dependency graph.

How do I detect CVE-2019-25102 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simple-markdown. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2019-25102 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2019-25102?

O3 pinpoints whether CVE-2019-25102 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2019-25102 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2019-25102, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2019-25102?

CVE-2019-25102 has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 61th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was CVE-2019-25102 published, and has it been updated?

CVE-2019-25102 was published on February 12, 2023 and was last updated on March 14, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2019-25102: Regular Expression Denial of Service in simple…

EPSS Exploitation Probability

via FIRST.org ↗

1.1%probability of exploitation in next 30 days

Lower Risk61th percentile+0.86%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

📦simple-markdown

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.

Description

A vulnerability, which was classified as problematic, was found in simple-markdown 0.6.0. Affected is an unknown function of the file simple-markdown.js. The manipulation with the input <<<<<<<<<<:/:/:/:/:/:/:/:/:/:/ leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 0.6.1 is able to address this issue. The patch is identified as 015a719bf5cdc561feea05500ecb3274ef609cd2. It is recommended to upgrade the affected component. VDB-220638 is the identifier assigned to this vulnerability.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`simple-markdown`	all versions	0.6.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simple-markdown. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update simple-markdown to 0.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-25102 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2019-25102 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2019-25102. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

A vulnerability, which was classified as problematic, was found in simple-markdown 0.6.0. Affected is an unknown function of the file simple-markdown.js. The manipulation with the input <<<<<<<<<<:/:/:/:/:/:/:/:/:/:/ leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 0.6.1 is able to address this issue. The patch is identified as 015a719bf5cdc561feea05500ecb3274ef609cd2. It is recommended to upgrade the affected component. VDB-220638 is the identifier assigned to th

O3 Security · Impact-Aware SCA

Is CVE-2019-25102 in your dependencies?

O3 detects CVE-2019-25102 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2019-25102