{"id":"CVE-2023-1732","aliases":["GHSA-2q89-485c-9j2x","GO-2023-1765"],"title":"Improper random reading in CIRCL","summary":"Improper random reading in CIRCL","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N","vendor":"cloudflare","product":"github.com/cloudflare/circl","ecosystem":"go","affected":["github.com/cloudflare/circl < 1.3.3"],"patched":["github.com/cloudflare/circl 1.3.3"],"published":"2023-05-11","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:49:54.418293155Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-2q89-485c-9j2x","references":[{"url":"https://github.com/cloudflare/circl/security/advisories/GHSA-2q89-485c-9j2x"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-1732"},{"url":"https://github.com/cloudflare/circl/commit/ff8d91225f8954b4970b6d6382d2e4c78f4a4cf8"},{"url":"https://github.com/cloudflare/circl"},{"url":"https://github.com/cloudflare/circl/releases/tag/v1.3.3"}],"tags":["osv","go"],"epss":0.00386,"epssPercentile":0.32558,"ingestedAt":"2026-07-09T18:56:35.448Z","slug":"CVE-2023-1732","body":"## Overview\n\n### Impact\nWhen 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.\n\nThe 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.\n\n\n### Patches\nThe fix was introduced in CIRCL v. 1.3.3\n\n\n## Affected packages\n\n- `github.com/cloudflare/circl < 1.3.3`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/cloudflare/circl 1.3.3`","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}