Posts

September 2024 Security Releases

By Ulises Gascón
29 Sep 2024

Recently, the Express team has been made aware of a number of security vulnerabilities in the Express project. We have released a number of patches to address these vulnerabilities.

Warning

We strongly recommend that you upgrade these modules to the recommended (or latest) version as soon as possible.

The following vulnerabilities have been addressed:

High severity vulnerability CVE-2024-45590 in body-parser middleware

body-parser version <1.20.3 is vulnerable to denial of service when URL-encoding is enabled

A malicious actor using a specially-crafted payload could flood the server with a large number of requests, resulting in denial of service.

Affected versions: <1.20.3

Patched versions: >=1.20.3

This vulnerability was discovered during the OSTIF audit to Express and was mitigated by the Express security triage team.

For more details, see GHSA-qwcr-r2fm-qrc7.

High severity vulnerability CVE-2024-47178 in basic-auth-connect middleware

basic-auth-connect uses a timing-unsafe equality comparison

basic-auth-connect <1.1.0 uses a timing-unsafe equality comparison that can leak timing information

Affected versions

Patched versions

This vulnerability was discovered during the OSTIF audit to Express and was mitigated by the Express Securty triage team.

More details area available in GHSA-7p89-p6hx-q4fw

Moderate severity vulnerability CVE-2024-43796 in Express core

The core express package is vulnerable to cross-site scripting (XSS) attack via response.redirect().

In Express version <4.20.0, passing untrusted user input—even after sanitizing it—to response.redirect() may execute untrusted code.

Affected versions:

Patched versions:

This vulnerability was discovered during the OSTIF audit of Express and was mitigated by the Express security triage team.

For more details, see GHSA-qw6h-vgh9-j6wx.

Moderate severity vulnerability CVE-2024-43799 in send utility module

The send utility module is vulnerable to template injection that can lead to vulnerability to cross-site scripting (XSS) attack.

Passing untrusted user input—even after sanitizing it—to SendStream.redirect() can execute untrusted code.

Affected versions: < 0.19.0

Patched versions: >=0.19.0

This vulnerability was discovered during the OSTIF audit of Express and was mitigated by the Express security triage team.

For more details, see GHSA-m6fv-jmcg-4jfg.

Moderate severity vulnerability CVE-2024-43800 in serve-static middleware

The serve-static middleware module is vulnerable to template injection that can lead to vulnerability to cross-site scripting (XSS) attack.

Passing untrusted user input—even after sanitizing it—to redirect() can execute untrusted code.

Affected versions:

Patched versions:

This vulnerability was discovered during the OSTIF audit of Express and was mitigated by the Express security triage team.

For more details, see GHSA-cm22-4g7w-348p

Moderate severity vulnerability CVE-2024-45296 in path-to-regexp utility module

The path-to-regexp utility module is vulnerable to regular expression denial of service (ReDoS) attack.

A bad regular expression is generated any time you have two parameters within a single segment, separated by something that is not a period (.). For example, /:a-:b.

Using /:a-:b will produce the regular expression /^\/([^\/]+?)-([^\/]+?)\/?$/. This can be exploited by a path such as /a${'-a'.repeat(8_000)}/a. OWASP has a good example of why this occurs, but in essence, the /a at the end ensures this route would never match, but due to naive backtracking it will still attempt every combination of the :a-:b on the repeated 8,000 -a.

Because JavaScript is single-threaded and regex matching runs on the main thread, poor performance will block the event loop and can lead to a DoS. In local benchmarks, exploiting the unsafe regex will result in performance that is over 1000x worse than the safe regex. In a more realistic environment, using Express v4 and ten concurrent connections results in an average latency of ~600ms vs 1ms.

Affected versions:

Patched versions:

Thanks to Blake Embrey who reported and created the security patch.

For more details, see GHSA-9wv6-86v2-598j