Spring Cloud Function CVE-2026-59298

Exploitation requires all of the following simultaneously: an authenticated session with high-privilege credentials (PR:H per CVSS vector), high attack complexity suggesting non-trivial, specific conditions must be met (AC:H), and a required user interaction (UI:R). The vulnerability is network-accessible via HTTP (AV:N), but the combination of authentication barrier, interaction dependency, and high complexity severely narrows the realistic attacker population. The description does not specify which configuration mode, adapter type, or specific header names trigger the improper filtering behavior - the precise triggering condition is unconfirmed. Limiting factors: high-privilege credentials must be obtained prior to exploitation; a user action during the attack is required; scope is unchanged (S:U), so cross-boundary escalation is not possible; and no availability impact is expected.

The CVSS 3.1 vector (AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:N) yields a Low severity score of 3.1, combining four compounding constraints: high attack complexity, high-privilege prerequisites, mandatory user interaction, and limited confidentiality and integrity impacts with no availability loss. No EPSS score was included in the source data, leaving exploitation probability unquantified, though the restrictive CVSS prerequisites make broad automated exploitation implausible. The vulnerability is absent from the CISA KEV catalog and no public proof-of-concept code has been identified - both signals favor low urgency. The realistic threat is narrow: an attacker would need valid high-privilege credentials and the ability to trigger a specific user interaction, ruling out opportunistic or unauthenticated attack paths. This is appropriate for standard patch-cycle remediation rather than emergency response.

An authenticated high-privilege operator or internal attacker sends a specially crafted HTTP request containing manipulated headers to a Spring Cloud Function endpoint; through the improper filtering flaw, these headers bypass validation and result in limited data exposure or minor integrity modification. The scenario requires both obtaining high-privilege credentials and engineering a user interaction event, constraining it to insider-threat or post-compromise contexts. No public proof-of-concept code is known, and high attack complexity further limits reproducibility.