# CVE-2026-33006: Apache HTTP Server: mod_auth_digest timing attack

> Remote attackers can bypass Digest authentication in Apache HTTP Server via a timing attack, requiring an upgrade to the latest version.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 May 2026
- **Updated:** 4 May 2026
- **Also known as:** ALPINE-CVE-2026-33006, AZL-86013, BELL-CVE-2026-33006, BIT-apache-2026-33006, DEBIAN-CVE-2026-33006, GHSA-r3x7-65m7-5p92, MINI-2g5r-j95r-7rrf, UBUNTU-CVE-2026-33006

## What is CVE-2026-33006?

CVE-2026-33006 is a medium-severity authentication bypass vulnerability in Apache Http Server, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A timing attack against mod_auth_digest in Apache HTTP Server 2.4.66 allows a bypass of Digest authentication by a remote attacker.

Users are recommended to upgrade to version 2.4.67, which fixes this issue.

Weakness: CWE-208 (Observable Timing Discrepancy)

## Which versions are affected by CVE-2026-33006?

1 open source package ship an affected version, including apache. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `apache` | Bitnami | All versions | 2.4.67 |

Products: Apache Http Server.

## How do I fix CVE-2026-33006?

Upgrade apache to 2.4.67 or later.

## Is CVE-2026-33006 being exploited?

There is no known exploitation of CVE-2026-33006 in the wild and no public exploit code.

Public exploit code:

- CTT-Enhanced Apache mod_auth_digest Timing Attack — CVE-2026-33006 Remote Digest Authentication Bypass → 33-Layer Temporal Timing Attack  Original vulnerability: Apache HTTP Server 2.4.66 (mod_auth_digest timing leak) CTVSS (Original): 4.8 (Medium) CTT-Enhanced CVSS: 7.5 (High) — Network, low complexity, temporal wedge evasion (github_poc): https://github.com/SimoesCTT/CTT-enhanced-Apache-mod_auth_digest-timing-attack-exploit

## Other vulnerabilities in Apache Http Server

- [CVE-2021-42013](https://insights.sbomify.com/CVE-2021-42013/): Apache HTTP Server Path Traversal (critical 9.8, exploited in the wild)
- [CVE-2024-38475](https://insights.sbomify.com/CVE-2024-38475/): Apache HTTP Server Improper Escaping of Output (critical 9.1, exploited in the wild)
- [CVE-2021-40438](https://insights.sbomify.com/CVE-2021-40438/): Apache HTTP Server-Side Request Forgery (SSRF) (critical 9.0, exploited in the wild)
- [CVE-2019-0211](https://insights.sbomify.com/CVE-2019-0211/): Apache HTTP Server Privilege Escalation (high 7.8, exploited in the wild)
- [CVE-2021-41773](https://insights.sbomify.com/CVE-2021-41773/): Apache HTTP Server Path Traversal (high 7.5, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33006 and fix it if it is affected.

What it is: CVE-2026-33006 is a medium-severity authentication bypass vulnerability in Apache Http Server, published on 4 May 2026. 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-2026-33006 in the wild and no public exploit code.

Affected packages and fixed versions:
- apache (Bitnami): affected all versions; fixed in 2.4.67

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-2026-33006/ (Markdown: https://insights.sbomify.com/CVE-2026-33006/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33006
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33006
- OSV: https://osv.dev/vulnerability/CVE-2026-33006

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33006/
Summaries are generated and may contain mistakes; the official description above is the record.