Linux kernel iSCSI initiator is widely used in servers/storage; overflow can enable kernel RCE or crash, risking broad enterprise disruption.
CVE-2026-74556
Linux kernel iSCSI initiator buffer overflow enabling potential RCE via malicious target
Is CVE-2026-74556 being exploited?
Not confirmed. CVE-2026-74556 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.40% probability of exploitation in the next 30 days.
How severe is CVE-2026-74556?
CVE-2026-74556 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-74556?
Yes. A fix has been recorded for CVE-2026-74556. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-74556 affect?
CVE-2026-74556 affects Linux kernel (libiscsi_tcp / iscsi initiator), open-iscsi clients, Enterprise servers using iSCSI initiators. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74556?
Apply kernel/open-iscsi patches immediately; restrict/block untrusted iSCSI targets and isolate iSCSI networks.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote kernel memory corruption from oversized SCSI Command Response, enabling possible remote code execution or host crash.
Immediate action required
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < a51812842084fd390590ab8dc0431f10c73ddc56
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < a8f94cc9f0e5759252551be3a172960c57f21f54
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < f1a3a51fc5dba0e99532379665069f1700da6b44
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < c97b5265cc47775f77fd2a23d6bde0426997b233
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < 084af0253673425ce2ae62e3c7f74f0dd023711b
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < 72815741715bd41556dac5eeb068bf0f8af06ee7
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < b0aa3e8e2ab4ca92adb28a3ef41873b3363b8676
- affected>= a081c13e39b5c17052a7b46fafa61019c4c110ff and < c1dea15f819cded9b3faf58f8bec72323568b6e6
- affected2.6.29
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.