Vulnerability in Linux kernel (CVE-2026-90414)
Summary
Vulnerability in Linux kernel (CVE-2026-90414). Confidential information can be exposed externally.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
IB/isert: reject PDUs declaring more data than was received
isert_recv_done() hands each received PDU to the opcode handlers without
ever looking at wc->byte_len, the number of bytes the HCA actually placed
in the receive descriptor. The handlers then copy that many bytes - the
data-segment length the initiator declared in the BHS
(ntoh24(hdr->dlength), via the derived unsol_data_len / imm_data_len) -
out of the fixed-size descriptor:
isert_handle_iscsi_dataout():
sg_copy_from_buffer(sg_start, sg_nents, isert_get_data(rx_desc),
unsol_data_len);
isert_handle_scsi_cmd():
sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents,
isert_get_data(rx_desc), imm_data_len);
Because the declared length is never checked against wc->byte_len, an
initiator can declare a data segment larger than the bytes it actually
sent (and larger than the descriptor) and cause an out-of-bounds read of
the receive buffer.
Nothing upstream of isert closes this door:
- __iscsit_check_dataout_hdr() bounds the inbound payload against
conn_ops->MaxXmitDataSegmentLength (MXDSL) - a transmit parameter,
used here for the inbound check. - iscsi_set_connection_parameters() sets
ops->MaxXmitDataSegmentLength = ops->TargetRecvDataSegmentLength;
and TARGETRECVDATASEGMENTLENGTH is absent from the min()-clamp list in
iscsi_check_acceptor_state(), so th…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-90414 has been found in Linux kernel.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-90414" on the vendor's site.
CVE-2026-90414 (Linux kernel) — CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-90414 linux Fixed in: 6.1.190-1
- Ubuntu UBUNTU-CVE-2026-90414 linux
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com