Red Hat Security Advisory: OpenShift Virtualization v4.12 Images
Affects Red HatSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in Red Hat package updates : patch Red Hat asn1 soon.
Data as of 3 Nov 2026, 04:44 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 7.5 |
|---|
- Patch
- Available – fixed in 1.27.0-rc.3, 1.26.6, 1.25.13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2 Nov 2026.
What to do
Upgrade encoding/asn1 to 1.27.0-rc.3, 1.26.6 or 1.25.13.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
Goencoding/asn1pkg:golang/encoding/asn1Other threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released updated OpenShift Virtualization v4.12 images that fix this vulnerability. Users should ensure all previously released errata are applied before updating to the fixed images. No other mitigations are currently available or recommended by Red Hat.
Description
CVE-2026-33818 is a denial of service vulnerability in the Go encoding/asn1 package used by Red Hat OpenShift Virtualization v4.12 images. An attacker can send a specially crafted, deeply nested ASN.1 structure that triggers excessive recursion during unmarshalling, causing stack exhaustion and service unavailability. This flaw can be exploited remotely without authentication. Red Hat has issued updated OpenShift Virtualization v4.12 images addressing this issue. No direct mitigation other than applying the update is currently recommended.