CVE-2021-41168

Summary

CVECVE-2021-41168
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-10-21 20:15:00 UTC
Updated2023-07-17 15:17:00 UTC
DescriptionSnudown is a reddit-specific fork of the Sundown Markdown parser used by GitHub, with Python integration added. In affected versions snudown was found to be vulnerable to denial of service attacks to its reference table implementation. References written in markdown ` [reference_name]: https://www.example.com` are inserted into a hash table which was found to have a weak hash function, meaning that an attacker can reliably generate a large number of collisions for it. This makes the hash table vulnerable to a hash-collision DoS attack, a type of algorithmic complexity attack. Further the hash table allowed for duplicate entries resulting in long retrieval times. Proofs of concept and further discussion of the hash collision issue are discussed on the snudown GHSA(https://github.com/reddit/snudown/security/advisories/GHSA-6gvv-9q92-w5f6). Users are advised to update to version 1.7.0.

Risk And Classification

Problem Types: CWE-407

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Reddit Snudown All All All All

References

ReferenceSourceLinkTags
Hash-collision denial-of-service vulnerabilities (#87) · reddit/snudown@1ac2c13 · GitHub MISC github.com
Hash-Collision Denial-of-Service Vulnerability in Reference Table · Advisory · reddit/snudown · GitHub CONFIRM github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

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