Libmodulemd: libmodulemd: missing decompressed-size limit when parsing compressed yaml
Summary
| CVE | CVE-2026-92823 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-21 04:18:12 UTC |
| Updated | 2026-10-30 07:16:34 UTC |
| Description | A flaw was found in libmodulemd. In builds with rpmio support enabled, compressed modulemd YAML is decompressed through a custom read handler that does not enforce a cumulative decompressed-size limit before parsing. An attacker who can supply a highly compressible compressed YAML file can cause excessive CPU and memory consumption, resulting in a denial of service. |
Risk And Classification
Primary CVSS: v3.1 6.2 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.001170000 probability, percentile 0.015920000 (date 2026-10-22)
Problem Types: CWE-409 | CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 6.2 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 6.2 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Hardened Images | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 5 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/security/cve/CVE-2026-92823 | [email protected] | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank AISLE Research for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-05-18T03:32:25.000Z | Reported to Red Hat. |
| CNA | 2026-10-21T03:02:56.516Z | Made public. |
Workarounds
CNA: Until a fix is available, avoid parsing attacker-controlled compressed module metadata in rpmio-enabled builds. Where compressed input is required, decompress outside the process under strict size quotas, or reject files whose decompressed size exceeds a conservative limit before passing data to libmodulemd. Building without rpmio support removes the affected path.