# CVE-2025-38700: scsi: libiscsi: Initialize iscsi_conn->dd_data only if memory is allocated

> A null pointer dereference in the Linux kernel iSER driver causes a system panic during connection teardown if memory allocation fails.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Sep 2025
- **Updated:** 12 May 2026
- **Also known as:** AZL-66905, AZL-73932, BELL-CVE-2025-38700, DEBIAN-CVE-2025-38700, GHSA-4vq4-24qf-gq5w, ROOT-OS-DEBIAN-11-CVE-2025-38700, ROOT-OS-DEBIAN-12-CVE-2025-38700, ROOT-OS-UBUNTU-2204-CVE-2025-38700, ROOT-OS-UBUNTU-2404-CVE-2025-38700, UBUNTU-CVE-2025-38700

## What is CVE-2025-38700?

CVE-2025-38700 is a medium-severity vulnerability in Debian Debian Linux, published on 4 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

scsi: libiscsi: Initialize iscsi_conn->dd_data only if memory is allocated

In case of an ib_fast_reg_mr allocation failure during iSER setup, the
machine hits a panic because iscsi_conn->dd_data is initialized
unconditionally, even when no memory is allocated (dd_size == 0).  This
leads invalid pointer dereference during connection teardown.

Fix by setting iscsi_conn->dd_data only if memory is actually allocated.

Panic trace:
------------
 iser: iser_create_fastreg_desc: Failed to allocate ib_fast_reg_mr err=-12
 iser: iser_alloc_rx_descriptors: failed allocating rx descriptors / data buffers
 BUG: unable to handle page fault for address: fffffffffffffff8
 RIP: 0010:swake_up_locked.part.5+0xa/0x40
 Call Trace:
  complete+0x31/0x40
  iscsi_iser_conn_stop+0x88/0xb0 [ib_iser]
  iscsi_stop_conn+0x66/0xc0 [scsi_transport_iscsi]
  iscsi_if_stop_conn+0x14a/0x150 [scsi_transport_iscsi]
  iscsi_if_rx+0x1135/0x1834 [scsi_transport_iscsi]
  ? netlink_lookup+0x12f/0x1b0
  ? netlink_deliver_tap+0x2c/0x200
  netlink_unicast+0x1ab/0x280
  netlink_sendmsg+0x257/0x4f0
  ? _copy_from_user+0x29/0x60
  sock_sendmsg+0x5f/0x70

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-38700?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38700?

Apply the vendor's patch.

## Is CVE-2025-38700 being exploited?

There is no known exploitation of CVE-2025-38700 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38700 and fix it if it is affected.

What it is: CVE-2025-38700 is a medium-severity vulnerability in Debian Debian Linux, published on 4 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-38700 in the wild and no public exploit code.

Affected product: Debian Debian Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-38700/ (Markdown: https://insights.sbomify.com/CVE-2025-38700/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38700
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38700
- OSV: https://osv.dev/vulnerability/CVE-2025-38700

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38700/
Summaries are generated and may contain mistakes; the official description above is the record.