CVE Intelligence
High

CVE-2026-98479 — scsi: libiscsi_tcp: Check the data direction of a Data-In PDU

In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi_tcp: Check the data direction of a Data-In PDU The Data-In branch of iscsi_tcp_hdr_dissect() resolves the ITT to a task and copies the PDU's data segment into that command's scatterlist without asking whether the command was reading. iscsi_tcp_r2t_rsp() in the same file does ask, and rejects an R2T for a command that is not DMA_TO_DEVICE. A target that answers a WRITE command's ITT with a Data-In therefore has the initiator write target-supplied bytes into the pages that write was about to send. Those are the caller's own pinned pages for an O_DIRECT write, and page cache pages for a buffered one. Observed against a test target that emits one 512-byte Data-In naming a 128 KB write's ITT, after the R2T for that write. With O_DIRECT the caller's buffer ends up holding 512 bytes of the target's data while pwrite() returns 131072. Buffered is quieter: pwrite() and fsync() both succeed, nothing is logged, and reading those blocks back returns the target's bytes out of the page cache without a command going on the wire. Check the direction before using the scatterlist, the way the R2T path already does.

Published Oct 18, 2026 · Updated Oct 24, 2026 · Sources: CVE Program (cve.org) e CISA ADP, NIST National Vulnerability Database, GitHub Security Advisories · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.4% (30-day exploitation probability)+5
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.39%
ahead of 33% of scored CVEs · Oct 30, 2026
Affects
Linux
Linux
CVSS base
7.5
High · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < 79991b770fc3685b1d5cf805b659a879edd19931≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < 8db1232945bc663fb94f300090a1fc108de99296≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < 94e5bdd08e51c450d954bc592f591c233ca5c9df≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < de96dc11aee0d058927bff94a168e3c5c46483e2≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < e3b25bf2cf2496e85bc05b33360faf9fdf880e03≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < ee56b5e18f566c0b5a183379dcd63d402cebf2f8≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < 24ffc919467d20951f0f132d1c75294e2e91e09b≥ a081c13e39b5c17052a7b46fafa61019c4c110ff and < bce07e2f37b5e4a427d36fd6b1c14067b27591db
and 1 more version 2.6.29
Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.5 CVSS 3.1 High 3.9 3.6 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database
7.5 CVSS 3.1 High — — Linux via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67)

EPSS over time FIRST

Oct 19, 2026 → Oct 30, 2026 · 12 reading(s) · max 0.39%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • CVSS changed · 7.5
    Oct 24, 2026 · NIST National Vulnerability Database
  • Source status changed · Published → Received
    Oct 18, 2026 · NIST National Vulnerability Database
  • Record published
    Oct 18, 2026
  • Affected products added · linux/linux
    Oct 18, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Published
    Oct 18, 2026 · CVE Program (cve.org) e CISA ADP
  • Record created in this database
    Oct 18, 2026 · Alertas do Telegram
  • CVE published
    Oct 18, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 18, 2026 – Oct 19, 2026
  • 1× Official description updated · Oct 18, 2026 – Oct 18, 2026

References

10 on the record

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

  • CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 3d
  • CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 3d
  • CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 3d
  • CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 3d
  • CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 3d
  • CVE-2026-99210 accel/rocket: clear rdev on device init failure 3d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No CISA SSVC assessment.
  • No CWE classification.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-98479 is "scsi: libiscsi_tcp: Check the data direction of a Data-In PDU", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.39% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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