Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Stephan Muelle libkcapi — Libkcapi: iv reuse in libkcapi one-shot symmetric cipher chunking causes cipher state reset across chunk boundaries
AV AC PR UI S C I A CVSS EPSS %ile KEV
N H N N U H L N 6.5 .0024 15.4 —
AFFECTED
Product Versions Fixed
libkcapi 0.10.1 – —
Red Hat Enterprise Linux 10 unspecified —
Red Hat Enterprise Linux 8 unspecified —
Red Hat Enterprise Linux 9 unspecified —
Red Hat Hardened Images unspecified —
Red Hat OpenShift Container Platform 4 unspecified —
TIMELINE
Aug 5 EXPLOIT PUBLISHED — CVE-2026-71225 (Stephan Muelle libkcapi). Public exploit reference added.
Aug 5 Reserved by redhat
Aug 5 Published (CNA: redhat)
Aug 11 EXPLOIT PUBLISHED — CVE-2026-71225 (Stephan Muelle libkcapi). Public exploit reference added.
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.
Lifecycle
Complete event history — 4 events, chronological
| Date | Event | Detail |
|---|
| August 5, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-71225 (Stephan Muelle libkcapi). Public exploit reference added. |
| August 5, 2026 | Reserved | Reserved by redhat |
| August 5, 2026 | Published | Published (CNA: redhat) |
| August 11, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-71225 (Stephan Muelle libkcapi). Public exploit reference added. |
Affected
Affected products and packages — 6 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| Stephan Muelle | libkcapi | — | 0.10.1 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | — |
| Red Hat | Red Hat Hardened Images | — | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-71225 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.