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CVE-2026-18249: IBM: Privilege escalation
CVE-2026-18249 is rated critical with a CVSS v3.1 base score of 9.9 and NVD lists IBM as the affected product. Per its scoring, it can be exploited over the network, without any user interaction.
Vulnerability description
IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote authenticated attacker to gain elevated privileges due to improper validation of pointers read from Java-controlled addresses.
Severity breakdown
CVSS v3.1 9.9: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: Low. A basic user account is enough.
- User interaction: None. No action from any user is needed.
- Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: Low. Reduced performance or intermittent interruption.
Underlying weakness
CWE-269: Improper Privilege Management
The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
Affected products
- IBM: 7.3; 7.4; 7.5; 7.6