CVE-2021-42836

GJSON before 1.9.3 allows a ReDoS (regular expression denial of service) attack.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Potential Mitigations

• Mitigation of resource exhaustion attacks requires that the target system either:

• The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

• The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/147.html
• https://cwe.mitre.org/data/definitions/227.html
• https://cwe.mitre.org/data/definitions/492.html

References

• https://github.com/tidwall/gjson/commit/590010fdac311cc8990ef5c97448d4fec8f29944
• https://github.com/tidwall/gjson/commit/77a57fda87dca6d0d7d4627d512a630f89a91c96
• https://github.com/tidwall/gjson/compare/v1.9.2...v1.9.3
• https://github.com/tidwall/gjson/issues/236
• https://github.com/tidwall/gjson/issues/237
• https://github.com/tidwall/gjson/commit/590010fdac311cc8990ef5c97448d4fec8f29944
• https://github.com/tidwall/gjson/commit/77a57fda87dca6d0d7d4627d512a630f89a91c96
• https://github.com/tidwall/gjson/compare/v1.9.2...v1.9.3
• https://github.com/tidwall/gjson/issues/236
• https://github.com/tidwall/gjson/issues/237