Vulnerability in open-iscsi (CVE-2026-18728)
Summary
Vulnerability in open-iscsi (CVE-2026-18728). Risk of unauthorized operations or information disclosure. Exploitable via iscsiuio.
Original description
The description as published by the source.
A flaw was found in open-iscsi. An integer underflow vulnerability in the iscsiuio component, specifically during IPv4 Dynamic Host Configuration Protocol (DHCP) parsing, allows a remote attacker on the same local network segment to cause a denial of service. By sending a specially crafted IPv4/UDP DHCP reply, the attacker can trigger an out-of-bounds read, leading to the iscsiuio process crashing. This issue affects systems where iscsiuio is actively handling IPv4 DHCP traffic.
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-2026-18728 has been found in open-iscsi.
Attackers can target a specific entry point like iscsiuio over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 6.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "open-iscsi CVE-2026-18728" on the vendor's site.
CVE-2026-18728 (open-iscsi) — CWE-191 / CVSS v3 6.5
Attack vector: adjacent-network / unauthenticated / no user interaction
Attack surface: iscsiuio
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 (CWE-191) exists in open-iscsi. Attackers reach the vulnerable code path via iscsiuio without authentication.
Check the vendor advisory for the affected versions of open-iscsi. Attack surface: iscsiuio.
Severity: Medium (CVSS 6.5/10). Risk of unauthorized operations or information disclosure.
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. Run grep -r 'open-iscsi' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'open-iscsi' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
open-iscsiを grep し、稼働しているサービス・バージョンを把握する。 -
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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-18728 open-iscsi Fixed in: 2.1.8-1+deb12u1
- Ubuntu UBUNTU-CVE-2026-18728 open-iscsi
References
- patch secalert@redhat.com
- patch secalert@redhat.com
- web nvd.nist.gov
- web github.com