Vulnerability Description
The Candid library causes a Denial of Service while parsing a specially crafted payload with 'empty' data type. For example, if the payload is `record { * ; empty }` and the canister interface expects `record { * }` then the Rust candid decoder treats empty as an extra field required by the type. The problem with the type empty is that the candid Rust library wrongly categorizes empty as a recoverable error when skipping the field and thus causing an infinite decoding loop. Canisters using affected versions of candid are exposed to denial of service by causing the decoding to run indefinitely until the canister traps due to reaching maximum instruction limit per execution round. Repeated exposure to the payload will result in degraded performance of the canister. Note: Canisters written in Motoko are unaffected.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Dfinity | Candid | >= 0.9.0, < 0.9.10 |
Related Weaknesses (CWE)
References
- https://github.com/dfinity/candid/blob/master/spec/Candid.mdProduct
- https://github.com/dfinity/candid/pull/478Patch
- https://github.com/dfinity/candid/security/advisories/GHSA-7787-p7x6-fq3jPatchThird Party Advisory
- https://internetcomputer.org/docs/current/references/candid-refProduct
- https://internetcomputer.org/docs/current/references/ic-interface-specProduct
- https://github.com/dfinity/candid/blob/master/spec/Candid.mdProduct
- https://github.com/dfinity/candid/pull/478Patch
- https://github.com/dfinity/candid/security/advisories/GHSA-7787-p7x6-fq3jPatchThird Party Advisory
- https://internetcomputer.org/docs/current/references/candid-refProduct
- https://internetcomputer.org/docs/current/references/ic-interface-specProduct
FAQ
What is CVE-2023-6245?
CVE-2023-6245 is a vulnerability with a CVSS score of 7.5 (HIGH). The Candid library causes a Denial of Service while parsing a specially crafted payload with 'empty' data type. For example, if the payload is `record { * ; empty }` and the canister interface expec...
How severe is CVE-2023-6245?
CVE-2023-6245 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2023-6245?
Check the references section above for vendor advisories and patch information. Affected products include: Dfinity Candid.