iskorotkov/avro: CPU Exhaustion in Avro Decoder
Summary
| CVE | CVE-2026-46385 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-29 20:16:27 UTC |
| Updated | 2026-07-30 12:18:52 UTC |
| Description | iskorotkov/avro is a fast Go Avro codec. Prior to 2.33.0, the Avro array and map decoders looped over an attacker-controlled block-count value without checking the underlying reader's error state inside the loop body. Reader.ReadBlockHeader returns the count as a Go int, which is 64-bit on amd64 / arm64 targets — so a producer can declare a block of up to math.MaxInt64 (~9.2 × 10¹⁸) elements followed by EOF (or any truncated payload), and the decoder will attempt that many no-op iterations before propagating the error. The realistic ceiling is "indefinite until the worker is killed externally" — a single hostile payload pins a CPU core until the process is OOM-killed, deadline-cancelled, or terminated. Remote, unauthenticated denial-of-service. This vulnerability is fixed in 2.33.0. |
Risk And Classification
Primary CVSS: v4.0 8.7 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.005040000 probability, percentile 0.402950000 (date 2026-07-31)
Problem Types: CWE-400 | CWE-835 | CWE-400 CWE-400: Uncontrolled Resource Consumption | CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | DECLARED | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| 3.1 | ADP | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Iskorotkov | Avro | affected < 2.33.0 | Not specified |
| ADP | Red Hat | Cryostat 4 On RHEL 9 | unaffected 4.2.0-19 * rpm | Not specified |
| ADP | Red Hat | Multicluster Global Hub 1.4.5 | unaffected 1784060681 * rpm | Not specified |
| ADP | Red Hat | Multicluster Global Hub 1.6.2 | unaffected 1784561376 * rpm | Not specified |
| ADP | Red Hat | Multicluster Global Hub 1.7.2 | unaffected 1784906628 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.11 | unaffected 1783578847 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.13 | unaffected 1782383730 * rpm | Not specified |
| ADP | Red Hat | Red Hat Multicluster Global Hub 1.5.0 | unaffected 1784562060 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Hardened Images | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46385.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:30651 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:47149 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-46385 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:44622 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| github.com/iskorotkov/avro/security/advisories/GHSA-w8j3-pq8g-8m7w | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | github.com | |
| access.redhat.com/errata/RHSA-2026:42852 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:41064 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| access.redhat.com/errata/RHSA-2026:41030 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:48151 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:40138 | MITRE | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-05-29T21:01:37.087Z | Reported to Red Hat. |
| ADP | 2026-05-29T19:58:59.667Z | Made public. |
Solutions
ADP: RHSA-2026:48151: Cryostat 4 on RHEL 9
ADP: RHSA-2026:41030: Multicluster Global Hub 1.4.5
ADP: RHSA-2026:44622: Multicluster Global Hub 1.6.2
ADP: RHSA-2026:47149: Multicluster Global Hub 1.7.2
ADP: RHSA-2026:41064: Red Hat Advanced Cluster Management for Kubernetes 2.11
ADP: RHSA-2026:30651: Red Hat Advanced Cluster Management for Kubernetes 2.13
ADP: RHSA-2026:42852: Red Hat multicluster global hub 1.5.0
Workarounds
ADP: Red Hat is not aware of a practical temporary workaround that fully mitigates this issue or meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the relevant security updates when they become available.