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No exploitation reported

CVE-2026-98479

scsi: libiscsi_tcp: Check the data direction of a Data-In PDU

No exploitation reported by the sources we read.

  • Published2026-10-18

Am I affected?

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Description

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.

Timeline

dates in UTC
  1. 2026-10-1816:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-24 15:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-98479?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-98479?format=csv
  • TAXII collection of exploited CVEs
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Versions per branch

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • CVE-2026-98479 Red Hat Product Security277 known affected

    kernel: scsi: libiscsi_tcp: Check the data direction of a Data-In PDU

    kernel as a component of Red Hat Enterprise Linux 10 · kernel-64k as a component of Red Hat Enterprise Linux 10 · kernel-64k-core as a component of Red Hat Enterprise Linux 10 · +274 more

Full record on NVD

Fix

  1. No fix available, says the vendor Red Hat Product Security CVE-2026-98479 · 263 productsFix deferred
  2. No fix planned, says the vendor Red Hat Product Security CVE-2026-98479 · 14 productsOut of support scope

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • NVDCVE recordread 2026-10-24
  • CNACVSS 3.17.5read 2026-10-24
  • FIRST EPSSEPSS score0.2 %2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Published
2026-10-18
Last Modified
2026-10-24
NVD status
Received

Frequently asked questions

What is CVE-2026-98479?

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.

Is CVE-2026-98479 actively exploited?

Active exploitation of CVE-2026-98479 has not been confirmed. Its EPSS score was 0.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-98479?

CVE-2026-98479 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

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