Vulnerability record · CVE-2020-27511 · published 21 June 2021
CVE-2020-27511: Prototypejs prototype vulnerability
Prototypejs · Prototype
An issue was discovered in the stripTags and unescapeHTML components in Prototype 1.7.3 where an attacker can cause a Regular Expression Denial of Service (ReDOS) through stripping crafted HTML tags.
Description
An issue was discovered in the stripTags and unescapeHTML components in Prototype 1.7.3 where an attacker can cause a Regular Expression Denial of Service (ReDOS) through stripping crafted HTML tags.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| http://prototypejs.org/ | Vendor Advisory |
| https://github.com/prototypejs/prototype/blob/dee2f7d8611248abce81287e1be4156011953c90/src/prototype/lang/string.js#L283 | ExploitThird Party Advisory |
| https://github.com/yetingli/PoCs/blob/main/CVE-2020-27511/Prototype.md | ExploitThird Party Advisory |
| http://prototypejs.org/ | Vendor Advisory |
| https://github.com/prototypejs/prototype/blob/dee2f7d8611248abce81287e1be4156011953c90/src/prototype/lang/string.js#L283 | ExploitThird Party Advisory |
| https://github.com/yetingli/PoCs/blob/main/CVE-2020-27511/Prototype.md | ExploitThird Party Advisory |
Track CVE-2020-27511 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2020-27511), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.
