CVE-2026-1015: IBM InfoSphere Information Server SSRF Flaw

CVE-2026-1015 Overview

CVE-2026-1015 is a Server-Side Request Forgery (SSRF) vulnerability affecting IBM InfoSphere Information Server versions 11.7.0.0 through 11.7.1.6. An authenticated attacker can abuse the flaw to coerce the server into issuing unauthorized HTTP requests to internal or external systems. Successful exploitation supports network enumeration, internal service discovery, and pivoting to additional attack chains against resources that are otherwise unreachable from the public network.

The weakness is tracked under CWE-918 (Server-Side Request Forgery). Attack complexity is low, requires low privileges, and produces limited impact on confidentiality and integrity with no impact on availability.

Critical Impact

An authenticated attacker can leverage the InfoSphere Information Server as a request proxy to enumerate internal networks and reach systems protected behind perimeter controls.

Affected Products

• IBM InfoSphere Information Server 11.7.0.0 through 11.7.1.6
• Deployments on IBM AIX
• Deployments on Linux and Microsoft Windows

Discovery Timeline

• 2026-03-25 - CVE-2026-1015 published to the National Vulnerability Database
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-1015

Vulnerability Analysis

The vulnerability resides in request-handling logic within IBM InfoSphere Information Server that accepts user-supplied URLs or host references and dispatches outbound requests without sufficient validation of the destination. Because the server performs the request on behalf of the authenticated user, the originating network identity becomes that of the InfoSphere host. This bypasses network segmentation that would normally block direct client-to-internal access.

The attacker must hold valid credentials, but no administrative role is required. The flaw affects confidentiality and integrity at a limited scope and does not directly degrade availability. The vulnerability spans IBM AIX, Linux, and Microsoft Windows installations because the issue exists in cross-platform application code rather than OS-level components.

Root Cause

The root cause is insufficient validation of destination URLs supplied to server-side request functions. Allow-listing of permitted hosts, schemes, and IP ranges is absent or incomplete. Internal addresses such as 127.0.0.1, 169.254.169.254, and RFC1918 ranges are not blocked, enabling requests to loopback services, cloud metadata endpoints, and internal management interfaces.

Attack Vector

Exploitation proceeds over the network against an authenticated session. The attacker submits a crafted request containing a target URL pointing to an internal resource. The server resolves the URL and issues the outbound request, returning response data, status codes, or timing information to the attacker. This response signal is sufficient to map open ports, identify internal services, and fingerprint hosts that are otherwise unreachable.

No verified public proof-of-concept code has been released for CVE-2026-1015. The EPSS probability score is 0.031%, indicating low predicted near-term exploitation activity. See the IBM Support Page for vendor-supplied technical details.

Detection Methods for CVE-2026-1015

Indicators of Compromise

• Outbound HTTP requests originating from the InfoSphere Information Server host to internal IP ranges or loopback addresses that fall outside normal application traffic patterns.
• Authenticated InfoSphere API or UI requests containing URL parameters that reference internal hostnames, cloud metadata endpoints, or non-standard ports.
• Application log entries showing repeated request failures or redirects against varying internal destinations from a single authenticated session.

Detection Strategies

• Correlate InfoSphere application logs with network flow telemetry to identify outbound connections that do not match documented integration endpoints.
• Inspect HTTP request bodies and query parameters reaching the InfoSphere server for URL-shaped values pointing at private address space.
• Baseline normal outbound destinations for the InfoSphere service account and alert on deviations such as connections to 169.254.169.254 or localhost ports.

Monitoring Recommendations

• Enable verbose access logging on the InfoSphere Information Server and forward logs to a centralized analytics platform for retention and query.
• Monitor authentication events for InfoSphere accounts exhibiting unusual session duration or high request volume against URL-accepting endpoints.
• Track egress traffic from InfoSphere hosts at the network layer and alert on connections to internal services not part of approved data flows.

How to Mitigate CVE-2026-1015

Immediate Actions Required

• Apply the fix referenced in the IBM advisory to all InfoSphere Information Server instances running 11.7.0.0 through 11.7.1.6.
• Audit InfoSphere user accounts and revoke or rotate credentials for accounts that are unused, over-privileged, or shared.
• Restrict outbound network access from InfoSphere hosts to only the destinations required for documented integrations.

Patch Information

IBM has published remediation guidance on the IBM Support Page for CVE-2026-1015. Administrators should review the advisory, identify the applicable interim fix or fix pack for their InfoSphere Information Server version, and schedule deployment through standard change control. Validate patch application by reviewing version metadata after installation.

Workarounds

• Place an egress proxy or firewall in front of InfoSphere hosts that enforces an allow-list of approved external destinations and blocks RFC1918 and link-local ranges.
• Disable or restrict access to InfoSphere features that accept user-supplied URLs until the patch is applied.
• Require multi-factor authentication for all InfoSphere accounts to raise the cost of credential-based exploitation.

# Example egress restriction using iptables to block link-local metadata access from the InfoSphere host
iptables -A OUTPUT -d 169.254.169.254 -j DROP
iptables -A OUTPUT -d 127.0.0.0/8 ! -o lo -j DROP
iptables -A OUTPUT -d 10.0.0.0/8 -m owner --uid-owner dsadm -j REJECT