CVE-2021-37606
Meow hash 0.5/calico does not sufficiently thwart key recovery by an attacker who can query whether there's a collision in the bottom bits of the hashes of two messages, as demonstrated by an attack against a long-running web service that allows the…
Does this matter?
Lower severity and a low EPSS score (0.74%). Track it; it rarely justifies an emergency change on its own.
Description
Meow hash 0.5/calico does not sufficiently thwart key recovery by an attacker who can query whether there's a collision in the bottom bits of the hashes of two messages, as demonstrated by an attack against a long-running web service that allows the attacker to infer collisions by measuring timing differences.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 0.74% probability · 54th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-203, CWE-326
- Affected
- meow hash project/meow hash
- Source
- cve@mitre.org
EPSS 0.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://news.ycombinator.com/item?id=27978878Third Party Advisory
- https://peter.website/meow-hash-cryptanalysisThird Party Advisory
- https://news.ycombinator.com/item?id=27978878Third Party Advisory
- https://peter.website/meow-hash-cryptanalysisThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.