CyberSecBulletin
CVE-2026-12148NVD status: Analyzed

MQ Operator: Deserialization of Untrusted Data

CVE-2026-12148 is a high-severity deserialization of untrusted data vulnerability in MQ Operator from IBM, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 3.4.0 as the first without the flaw, so updating MQ Operator to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update MQ Operator to 3.4.0 or a later version.
  2. Read the advisory on ibm.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
IBMMQ Operator3.2.0 through 3.2.29; 3.3.0 up to, but not including, 3.4.0; 3.4.1; 3.5.0; 3.5.1 through 3.5.3; 3.6.0 through 3.6.4; 3.7.0 through 3.7.2; 3.8.0; and 10 more ranges3.4.0
IBMMQ Advanced container images9.4.0.6-r1; 9.4.0.6-r2; 9.4.0.7-r1; 9.4.0.10-r1; 9.4.0.10-r2; 9.4.0.11-r1; 9.4.0.11-r2; 9.4.0.11-r3; and 32 more rangesNot stated
IBMSupplied Mq Advanced Container Images9.4.1.0; 9.4.1.1; 9.4.2.0; 9.4.2.1; 9.4.3.0; 9.4.3.1; 9.4.4.0; 9.4.4.1; and 32 more rangesNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (us.ibm.com)
CVSS 3.18.8HighNVD

Official description

IBM MQ Operator could allow an authenticated attacker to cause a denial of service or potentially execute arbitrary code due to unrestricted Java deserialization in the MQ Classes for Java.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in MQ Operator

All MQ Operator vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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