# CVE-2025-26618: SSH SFTP packet size not verified properly in Erlang OTP

> Authenticated users can cause excessive memory allocation in Erlang OTP SFTP server by sending crafted SSH packets, leading to denial of service.

- **Severity:** High 7.0 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 20 Feb 2025
- **Updated:** 3 Nov 2025
- **Also known as:** AZL-57083, AZL-57095, DEBIAN-CVE-2025-26618, GHSA-78cv-45vx-q6fr, MGASA-2025-0088, OESA-2025-1220, SUSE-SU-2025:0901-1, SUSE-SU-2025:1051-1, UBUNTU-CVE-2025-26618, USN-7313-1, openSUSE-SU-2025:14879-1

## What is CVE-2025-26618?

CVE-2025-26618 is a high-severity denial of service vulnerability in erlang otp, published on 20 Feb 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Erlang is a programming language and runtime system for building massively scalable soft real-time systems with requirements on high availability. OTP is a set of Erlang libraries, which consists of the Erlang runtime system, a number of ready-to-use components mainly written in Erlang. Packet size is not verified properly for SFTP packets. As a result when multiple SSH packets (conforming to max SSH packet size) are received by ssh, they might be combined into an SFTP packet which will exceed the max allowed packet size and potentially cause large amount of memory to be allocated. Note that situation described above can only happen for successfully authenticated users after completing the SSH handshake. This issue has been patched in OTP versions 27.2.4, 26.2.5.9, and 25.3.2.18. There are no known workarounds for this vulnerability.

Weakness: CWE-789 (Memory Allocation with Excessive Size Value)

## Which versions are affected by CVE-2025-26618?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `erlang` | SUSE:Linux Enterprise Module for Server Applications 15 SP6 | All versions | 23.3.4.19-150300.3.17.1 |
| `erlang26` | SUSE:Linux Enterprise Module for Server Applications 15 SP6 | All versions | 26.2.1-150300.7.8.1 |
| `erlang` | openSUSE:Leap 15.6 | All versions | 23.3.4.19-150300.3.17.1 |
| `erlang26` | openSUSE:Leap 15.6 | All versions | 26.2.1-150300.7.8.1 |
| `erlang` | openSUSE:Tumbleweed | All versions | 27.2.4-2.1 |

## How do I fix CVE-2025-26618?

Upgrade to a fixed version.

## Is CVE-2025-26618 being exploited?

There is no known exploitation of CVE-2025-26618 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-26618 and fix it if it is affected.

What it is: CVE-2025-26618 is a high-severity denial of service vulnerability in erlang otp, published on 20 Feb 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-26618 in the wild and no public exploit code.

Affected product: erlang otp. 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-2025-26618/ (Markdown: https://insights.sbomify.com/CVE-2025-26618/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-26618
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-26618
- OSV: https://osv.dev/vulnerability/CVE-2025-26618

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-26618/
Summaries are generated and may contain mistakes; the official description above is the record.