Description
A flaw was found in libkcapi. When performing one-shot symmetric cipher operations on large inputs (over 64 KiB) in stateful modes such as Counter (CTR) or Cipher Block Chaining (CBC), the library improperly reuses the Initialization Vector (IV) for each internal data chunk. A remote attacker could potentially exploit this by making an application that uses libkcapi process specially crafted large inputs. This can lead to a significant weakening of data confidentiality, as the repeated IV use can expose relationships in encrypted plaintext, and may also affect data integrity by causing incorrect cryptographic processing.
Affected products
redhat: hardened images; redhat: openshift container platform; smuellerdd: libkcapi; redhat: enterprise linux
References8
- access.redhat.com/security/cve/CVE-2026-71225 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2462011 ExploitIssue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:56985
- access.redhat.com/errata/RHSA-2026:67265
- access.redhat.com/errata/RHSA-2026:67266
- access.redhat.com/errata/RHSA-2026:67267
- access.redhat.com/errata/RHSA-2026:69285
- access.redhat.com/errata/RHSA-2026:87712
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N - EPSS — exploit probability
- 0% percentile: 29 · as of 13 November 2026
- CWE
- CWE-330
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