Improper input validation in Cloudflare Circl
CVE-2023-1732
When sampling randomness for a shared secret, the implementation of Kyber and FrodoKEM, did not check whether crypto/rand.Read() returns an error. In rare deployment cases (error thrown by the Read() function), this could lead to a predictable shared secret. The tkn20 and blindrsa components did not check whether enough randomness was returned from the user provided randomness source. Typically the user provides crypto/rand.Reader, which in the vast majority of cases will always return the right number random bytes. In the cases where it does not, or the user provides a source that does not, the blinding for blindrsa is weak and integrity of the plaintext is not ensured in tkn20.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (30.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Cloudflare Circl — versions 0
Weakness classification (CWE)
References
- github.com/cloudflare/circl/security/advisories/GHSA-2q89-485c-9j2x (Vendor Advisory)
Frequently asked questions
- What is CVE-2023-1732?
- CVE-2023-1732 is a medium-severity vulnerability in Cloudflare Circl, classified under Improper Input Validation. CVSS score: 5.3/10. Published 2023-05-10.
- How severe is CVE-2023-1732?
- Medium severity. CVSS v3 base score is 5.3 out of 10.