CVE-2020-26302 is_js vulnerable to Regular Expression Denial of Service
Attackers can cause denial of service in applications using is.js by submitting malicious strings that trigger inefficient regular expressions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2020-26302?
CVE-2020-26302 is a high-severity denial of service vulnerability in arasatasaygin is.js, published on 23 Dec 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
is.js is a general-purpose check library. Versions 0.9.0 and prior contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). is.js uses a regex copy-pasted from a gist to validate URLs. Trying to validate a malicious string can cause the regex to loop “forever." This vulnerability was found using a CodeQL query which identifies inefficient regular expressions. is.js has no patch for this issue.
Which versions are affected by CVE-2020-26302?
2 open source packages ship an affected version, including is_js. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
is_js npm | All versions to 0.9.0 | None |
is_js npm | All versions to 0.9.0 | None |
Products include Is.js Project Is.js.
How do I fix CVE-2020-26302?
No fix has been published for CVE-2020-26302 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2020-26302 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-26302 exists.
Sources
Also known as GHSA-pvrw-g6fx-mcx2.