Vulnerability in Red Hat Confidential Compute Attestation
CVE-2026-42784
A flaw was found in sequoia-openpgp. The library incorrectly infers key flags for older certificates when a key flags subpacket is missing, leading to a discrepancy in how key capabilities are viewed. This key flag confusion allows an attacker to bypass the back-signature check. Consequently, an attacker can illegitimately bind an arbitrary subkey to their own certificate and forge signatures, completely compromising cryptographic integrity.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (24.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-42784 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- access.redhat.com/errata/RHSA-2026:42902 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:76734 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:76733 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:76735 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:76737 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:79357 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:34160 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:42078 (vendor-advisory)
Frequently asked questions
- What is CVE-2026-42784?
- CVE-2026-42784 is a high-severity vulnerability in Red Hat Confidential Compute Attestation, classified under Improper Verification of Cryptographic Signature. CVSS score: 7.4/10. Published 2026-09-16.
- How severe is CVE-2026-42784?
- High severity. CVSS v3 base score is 7.4 out of 10.