# CVE-2023-3446: Excessive time spent checking DH keys and parameters

> Attackers can cause denial of service by supplying excessively long DH keys to applications using OpenSSL's DH_check functions.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2023
- **Updated:** 14 Oct 2026
- **Also known as:** ALPINE-CVE-2023-3446, ALSA-2024:0888, AZL-42955, AZL-47646, CLEANSTART-2026-TF51125, CLSA-2023-1700593531, CLSA-2023-1700593692, CLSA-2025-1758635382, CLSA-2026-1772151043, DEBIAN-CVE-2023-3446, GHSA-3p3x-vg38-6g9q, OESA-2023-1466, RHSA-2024:0888, SUSE-SU-2023:2961-1, SUSE-SU-2023:2962-1, SUSE-SU-2023:2964-1, SUSE-SU-2023:2965-1, SUSE-SU-2023:2972-1, SUSE-SU-2023:2973-1, SUSE-SU-2023:3012-1, SUSE-SU-2023:3093-1, SUSE-SU-2023:3160-1, UBUNTU-CVE-2023-3446, openSUSE-SU-2024:13064-1, openSUSE-SU-2024:13070-1

## What is CVE-2023-3446?

CVE-2023-3446 is a medium-severity denial of service vulnerability in Openssl Openssl, published on 19 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Issue summary: Checking excessively long DH keys or parameters may be very slow.

Impact summary: Applications that use the functions DH_check(), DH_check_ex()
or EVP_PKEY_param_check() to check a DH key or DH parameters may experience long
delays. Where the key or parameters that are being checked have been obtained
from an untrusted source this may lead to a Denial of Service.

The function DH_check() performs various checks on DH parameters. One of those
checks confirms that the modulus ('p' parameter) is not too large. Trying to use
a very large modulus is slow and OpenSSL will not normally use a modulus which
is over 10,000 bits in length.

However the DH_check() function checks numerous aspects of the key or parameters
that have been supplied. Some of those checks use the supplied modulus value
even if it has already been found to be too large.

An application that calls DH_check() and supplies a key or parameters obtained
from an untrusted source could be vulernable to a Denial of Service attack.

The function DH_check() is itself called by a number of other OpenSSL functions.
An application calling any of those other functions may similarly be affected.
The other functions affected by this are DH_check_ex() and
EVP_PKEY_param_check().

Also vulnerable are the OpenSSL dhparam and pkeyparam command line applications
when using the '-check' option.

The OpenSSL SSL/TLS implementation is not affected by this issue.
The OpenSSL 3.0 and 3.1 FIPS providers are not affected by this issue.

Weakness: CWE-1333 (Inefficient Regular Expression Complexity), CWE-606 (Unchecked Input for Loop Condition)

## Which versions are affected by CVE-2023-3446?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `edk2-aarch64` | AlmaLinux:8 | All versions | 20220126gitbb1bba3d77-6.el8_9.3 |
| `edk2-ovmf` | AlmaLinux:8 | All versions | 20220126gitbb1bba3d77-6.el8_9.3 |
| `edk2` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20220126gitbb1bba3d77-6.el8_9.3 |
| `edk2-aarch64` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20220126gitbb1bba3d77-6.el8_9.3 |
| `edk2-ovmf` | Red Hat:enterprise_linux:8::appstream | All versions | 0:20220126gitbb1bba3d77-6.el8_9.3 |
| `openssl-1_0_0` | SUSE:Enterprise Storage 7 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Enterprise Storage 7.1 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 1.1.0i-150100.14.59.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOS | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Micro 5.3 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Micro 5.4 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Module for Basesystem 15 SP4 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Module for Basesystem 15 SP5 | All versions | 1.1.1l-150500.17.9.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Module for Legacy 15 SP4 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Module for Legacy 15 SP5 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl` | SUSE:Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | All versions | 0.9.8j-0.106.77.1 |
| `openssl1` | SUSE:Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | All versions | 1.0.1g-0.58.73.1 |
| `openssl` | SUSE:Linux Enterprise Server 12 SP2-BCL | All versions | 1.0.2j-60.101.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.0.2p-3.81.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 1.1.1d-2.92.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 1.1.0i-150100.14.59.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.0.2p-3.81.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 1.1.1d-2.92.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Server for SAP Applications 15 SP1 | All versions | 1.1.0i-150100.14.59.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_0_0` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 1.0.2p-3.81.1 |
| `openssl-1_1` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 1.1.1d-2.92.1 |
| `openssl-1_0_0` | openSUSE:Leap 15.4 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | openSUSE:Leap 15.4 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_0_0` | openSUSE:Leap 15.5 | All versions | 1.0.2p-150000.3.82.1 |
| `openssl-1_1` | openSUSE:Leap 15.5 | All versions | 1.1.1l-150500.17.9.1 |
| `openssl-1_1` | openSUSE:Leap Micro 5.3 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_1` | openSUSE:Leap Micro 5.4 | All versions | 1.1.1l-150400.7.48.1 |
| `openssl-1_0_0` | openSUSE:Tumbleweed | All versions | 1.0.2u-21.1 |

Products: Openssl Openssl.

## How do I fix CVE-2023-3446?

Apply the vendor's patch.

## Is CVE-2023-3446 being exploited?

There is no known exploitation of CVE-2023-3446 in the wild and no public exploit code.

## Other vulnerabilities in Openssl Openssl

- [CVE-2009-3245](https://insights.sbomify.com/CVE-2009-3245/): Null dereference in n/a (critical 10.0)
- [CVE-2006-3738](https://insights.sbomify.com/CVE-2006-3738/): Memory corruption in n/a (critical 10.0)
- [CVE-2026-63073](https://insights.sbomify.com/CVE-2026-63073/): Untrusted Sender DN Used as Format String in CMP Response Validation (critical 9.8)
- [CVE-2016-6309](https://insights.sbomify.com/CVE-2016-6309/): Use after free in n/a (critical 9.8)
- [CVE-2016-0799](https://insights.sbomify.com/CVE-2016-0799/): Integer overflow in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-3446 and fix it if it is affected.

What it is: CVE-2023-3446 is a medium-severity denial of service vulnerability in Openssl Openssl, published on 19 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-3446 in the wild and no public exploit code.

Affected product: Openssl Openssl. 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-2023-3446/ (Markdown: https://insights.sbomify.com/CVE-2023-3446/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-3446
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-3446
- OSV: https://osv.dev/vulnerability/CVE-2023-3446

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-3446/
Summaries are generated and may contain mistakes; the official description above is the record.
