{"id":"CVE-2026-6458","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-6458","generatedAt":"2026-10-28T03:26:34.826Z","title":"Missing cryptographic step in Caliptra Core Firmware (aes_256_gcm_update module) results in an incorrect GCM authentication tag.","description":"Missing cryptographic step in Caliptra Core Firmware (aes_256_gcm_update module) results in an incorrect GCM authentication tag. When the streaming AES-256-GCM API is used with empty AAD, the hardware GHASH accumulator state is not saved after the first update call, causing the final tag to exclude the first batch of processed ciphertext. Ciphertext produced by that call may be modified without the tag reflecting the change.\n\nThis issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.","published":"2026-06-24T00:16:34.000Z","lastModified":"2026-10-25T23:10:00.000Z","status":"Awaiting Analysis","sourceIdentifier":"b01ddd03-5ef6-483b-b2c5-acba77f1a554","cvss":{"version":"4.0","score":5.1,"severity":"MEDIUM","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-325"],"affected":[],"epss":{"score":0.00197,"percentile":0.09343,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-834g-h5x6-2hqr","source":"b01ddd03-5ef6-483b-b2c5-acba77f1a554"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-6458","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}