CVE-2021-43843 Insufficient patch for Regular Expression Denial of Service (ReDoS) to jsx-slack v4.5.1

2021-12-2021:15:12

CWE-1333

CWE-400

GitHub_M

www.cve.org

5.3 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

LOW

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

0.002 Low

EPSS

Percentile

61.1%

JSON

jsx-slack is a package for building JSON objects for Slack block kit surfaces from JSX. The maintainers found the patch for CVE-2021-43838 in jsx-slack v4.5.1 is insufficient tfor protection from a Regular Expression Denial of Service (ReDoS) attack. If an attacker can put a lot of JSX elements into <blockquote> tag with including multibyte characters, an internal regular expression for escaping characters may consume an excessive amount of computing resources. v4.5.1 passes the test against ASCII characters but misses the case of multibyte characters. jsx-slack v4.5.2 has updated regular expressions for escaping blockquote characters to prevent catastrophic backtracking. It is also including an updated test case to confirm rendering multiple tags in <blockquote> with multibyte characters.

CNA Affected

[
  {
    "product": "jsx-slack",
    "vendor": "yhatt",
    "versions": [
      {
        "status": "affected",
        "version": "< 4.5.2"
      }
    ]
  }
]