IBM Cognos Controller CVE-2025-36326

No special configuration is required - all deployments of IBM Cognos Controller 11.0.0-11.0.1 and IBM Controller 11.1.0-11.1.1 ship with the same hardcoded cryptographic key used to sign session cookies, so default installations are affected. The practical limiting factor is that an attacker must first obtain or derive this static signing key (recoverable from the product software/binaries, but not published in the referenced advisory) before they can forge a trusted cookie; network reachability of the application's session endpoint is also required.

Signals are mixed and lean toward moderate, not urgent, priority. The IBM-supplied CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/C:H/I:N/A:N, 7.5 HIGH) describes a remotely reachable, low-complexity, no-privilege, no-interaction confidentiality-only flaw, which on paper is attractive to attackers. However, EPSS is very low at 0.03% (7th percentile), the CVE is NOT on CISA KEV, and no public exploit or POC is referenced - so there is no public exploit identified at time of analysis and no evidence of active exploitation. The CWE-321 nature (hardcoded cryptographic keys for signing session cookies) means practical exploitation hinges on an attacker first recovering the static key from the product, which tempers the raw PR:N optimism even though it is not reflected as added attack complexity. Net: a credible confidentiality weakness worth patching in affected IBM Cognos Controller / Controller instances, but the low EPSS and absence of KEV/POC suggest this is not currently seeing widespread opportunistic exploitation. Note one reconcilable tension: CVSS marks I:N, yet forged session cookies could in principle enable session impersonation (an integrity/authentication concern) - verify intended impact scope with IBM advisory node 7246015.

An attacker who has extracted the hardcoded cookie-signing key (identical across all deployments of the affected versions) crafts a validly signed session cookie and presents it to a target IBM Cognos Controller or IBM Controller instance over the network. Because the server trusts any cookie signed with that static key, the attacker can impersonate a session and read sensitive financial/consolidation data without authenticating. No public exploit code is referenced, so this would require attacker-developed tooling against the known key.