IBM Concert CVE-2025-36084

Exploitation requires the attacker to first acquire data that IBM Concert (versions 1.0.0 through 3.0.0) encrypted using the weaker-than-expected algorithm, then successfully break that algorithm to recover plaintext. There is no special product configuration named in the advisory - the weakness is inherent to the affected versions' cryptographic choice. The primary limiting factor is attack complexity (CVSS AC:H): the attacker needs access to the ciphertext and must invest cryptanalytic or brute-force effort, so this is not a single-request remote compromise. No authentication is required per the vector (PR:N) and no user interaction (UI:N), but the practical dependency on obtaining protected data constrains real-world exploitation.

This is a moderate-severity, confidentiality-only cryptographic weakness (CWE-327) in IBM Concert 1.0.0 through 3.0.0. The vendor CVSS 3.1 vector (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N = 5.9) is internally consistent with the description: network vector and no privileges (PR:N) reflect that the flaw is a design-level weak-algorithm choice, while AC:H correctly captures that exploitation is not trivial - an attacker must obtain the protected ciphertext and then defeat the weak algorithm through cryptanalysis or brute force rather than simply reading a value. Impact is confidentiality-only (C:H, I:N, A:N), matching the 'decrypt highly sensitive information' description. No EPSS score, SSVC decision, or POC is provided in the input, and this is not on the CISA KEV list, so there is no public exploit identified at time of analysis and no evidence of active exploitation. Net: this is a real but lower-priority issue - the high confidentiality impact is tempered by the meaningful attack complexity (AC:H) and the practical prerequisite of already having access to the encrypted data. Treat it as a patch-in-normal-cycle item rather than an emergency, driven mostly by the sensitivity of data Concert stores.

An attacker who intercepts or otherwise obtains data that IBM Concert protected with the weak algorithm (for example from network capture, a backup, or a compromised store) performs offline cryptanalysis or brute-force against the substandard cipher to recover the plaintext of highly sensitive information. The AC:H rating reflects that this requires effort and access to the ciphertext rather than a single trivial request, and no public proof-of-concept is available.