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CVE-2024-56586 Linux CVE debrief

CVE-2024-56586 describes a bug in the Linux F2FS (Flash-Friendly File System) where a specific sequence of operations—creating large files while checkpointing is disabled until space exhaustion, deleting those files, remounting to re-enable checkpointing, and then unmounting—triggers an f2fs_bug_on assertion during the f2fs_evict_inode call. This vulnerability was originally identified in the Linux kernel and affects Siemens industrial networking products that incorporate the vulnerable F2FS implementation within their underlying operating system. The CISA ICS advisory ICSA-25-226-07, which republished Siemens' SSA-355557 security advisory, initially listed this CVE as affecting certain Siemens products. However, subsequent analysis and advisory updates led to this CVE being marked as 'Misinformed' in the threat data, indicating that the affected products were incorrectly identified or that the vulnerability does not actually impact the listed Siemens products as originally assessed. The advisory underwent multiple revisions between February 2026, with the final update on February 25, 2026, clarifying product impact status. No CVSS score or severity rating is currently assigned to this CVE. Organizations should verify their specific product configurations against the latest Siemens ProductCERT advisory to confirm actual exposure, as the threat categorization suggests the initial impact assessment was erroneous.

Vendor
Linux
Product
RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2025-08-12
Original CVE updated
2026-02-25
Advisory published
2025-08-12
Advisory updated
2026-02-25

Who should care

Organizations running Siemens RUGGEDCOM RST2428P or SCALANCE XC/XR/XCM/XRM/XCH/XRH industrial networking products should verify current advisory status, as this CVE was marked 'Misinformed' and may not require action. Linux system administrators using F2FS with checkpoint disable/enable workflows should monitor kernel security updates. Industrial control system operators should follow CISA recommended practices for defense in depth regardless of this specific CVE status.

Technical summary

The vulnerability exists in the F2FS (Flash-Friendly File System) implementation in the Linux kernel. The bug is triggered through a specific sequence: (1) disable filesystem checkpointing, (2) create large files until storage space is exhausted, (3) delete those files, (4) remount the filesystem with checkpointing re-enabled, and (5) unmount the filesystem. This sequence causes an f2fs_bug_on assertion failure in the f2fs_evict_inode function during unmount. The vulnerability was initially reported as affecting Siemens RUGGEDCOM and SCALANCE industrial networking products, but subsequent CISA/Siemens analysis reclassified the impact as 'Misinformed,' indicating the products are not actually vulnerable. The root cause is a logic error in F2FS inode eviction handling when checkpoint state transitions occur under specific disk space conditions. No privilege escalation or remote exploitation pathway is described; this is a local filesystem consistency issue that may cause denial of service (system panic/bug check) during unmount operations.

Defensive priority

low

Recommended defensive actions

  • Verify current product impact status by consulting the latest Siemens ProductCERT SSA-355557 advisory before prioritizing remediation efforts
  • Review CISA ICS recommended practices for industrial control systems defense in depth strategies
  • Monitor CISA ICS advisories for any future updates to ICSA-25-226-07 regarding this CVE
  • Apply standard Linux kernel security updates through vendor channels if F2FS filesystem is used in custom deployments
  • Document any local F2FS usage with checkpoint disable/enable workflows for security review

Evidence notes

The source CISA CSAF advisory ICSA-25-226-07 explicitly categorizes this CVE's impact as 'Misinformed' in the threats section, indicating the vulnerability does not actually affect the listed Siemens products. The advisory revision history shows multiple updates between February 12-25, 2026, correcting affected product lists and removing rejected CVEs. The CVE description describes a Linux kernel F2FS filesystem bug, not a Siemens-specific vulnerability.

Official resources

2025-08-12