CVE-2023-54356 — Kyverno before 1.9.5 Sweet32 Medium Strength Cipher Suites
Kyverno versions 1.9.4 and earlier support insecure 3DES cipher suites (TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA and TLS_RSA_WITH_3DES_EDE_CBC_SHA) on their TLS endpoints. These 64-bit block ciphers are vulnerable to the Sweet32 attack (CVE-2016-2183), which, over very long-lived TLS connections carrying large volumes of traffic, could allow an attacker to recover small amounts of plaintext. The issue is fixed in Kyverno 1.9.5 and 1.10.0.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Kyverno Kyverno).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 9.3 | CVSS 4.0 | Critical | — | — | disclosure@vulncheck.com via NIST National Vulnerability Database |
| 9.3 | CVSS 4.0 | Critical | — | — | VulnCheck via CVE Program (cve.org) e CISA ADP |
| 3.7 | CVSS 3.1 | Low | 2.2 | 1.4 | disclosure@vulncheck.com via NIST National Vulnerability Database |
| 3.7 | CVSS 3.1 | Low | — | — | VulnCheck via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N (score shown at the top: disclosure@vulncheck.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.15%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Check TLS negotiations and unexpected certificates in the component’s traffic.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · kyverno/kyverno
- SSVC assessment updated
- Record published
- CVSS changed · 3.7
- Source status changed · → Awaiting Analysis
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-84199 Kyverno before 1.16.2 SSRF via APICall Feature Sep 1, 2026
- Medium CVE-2026-44245 Kyverno: [policy-reporter-ui] XSS via Stored Property Values in PropertyCard Component May 12, 2026
- High CVE-2026-41485 Kyverno Controller Denial of Service via forEach Mutation Panic Apr 24, 2026
- Critical CVE-2026-41323 Kyverno: ServiceAccount token leaked to external servers via apiCall service URL Apr 24, 2026
- High CVE-2026-41068 Kyverno: Cross-Namespace Read Bypasses RBAC Isolation (CVE-2026-22039 Incomplete Fix) Apr 24, 2026
- High CVE-2026-40868 kyverno apicall servicecall implicit bearer token injection leaks kyverno serviceaccount token Apr 21, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2023-54356 is "Kyverno before 1.9.5 Sweet32 Medium Strength Cipher Suites", rated Low. It affects Kyverno (Kyverno); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 3.7 describes technical severity. EPSS 0.15% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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