dbcve.org
HTTP ServerWeb server / proxy · Apache

CVE-2026-33007

MEDIUM · 5.3 CVSS v3.1 Published 2026-05-04
Fix available
A fix is available. Upgrade to 2.4.67 or later.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A NULL pointer dereference in the mod_authn_socache in Apache HTTP Server 2.4.66 and earlier allows an unauthenticated remote user to crash a child process in a caching forward proxy configuration. Users are recommended to upgrade to version 2.4.67, which fixes this issue.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A NULL pointer dereference vulnerability in mod_authn_socache module of Apache HTTP Server 2.4.66 and earlier allows unauthenticated remote attackers to crash child processes specifically in caching forward proxy configurations, resulting in denial of service.

MitigationUpgrade Apache HTTP Server to version 2.4.67 or later. Until upgrade is possible, consider disabling the caching forward proxy configuration or restricting network access to reduce exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
HTTP ServerWeb server / proxy
Affected:>= 2.4.0, < 2.4.67

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed Apache HTTP Server version
    Run 'httpd -v' or 'apache2 -v' to get the server version
    Affected if Version is 2.4.0 or higher but lower than 2.4.67
  2. Verify mod_authn_socache module is loaded
    Run 'httpd -M' or 'apache2ctl -M' and grep for 'authn_socache', or check configuration files for 'LoadModule authn_socache_module'
    Affected if The module is loaded and in use
  3. Identify if caching forward proxy is configured
    Search configuration files (httpd.conf, included conf files) for ProxyCache directives or similar caching proxy settings combined with authentication
    Affected if A caching forward proxy configuration exists that uses mod_authn_socache for authentication caching
  4. Confirm proxy and authentication relationship
    Review proxy-related directives (ProxyPass, ProxyRemote) and authentication configuration (AuthType, Require) to see if authentication caching is applied to proxy requests
    Affected if Proxy requests are configured to use authenticated user caching via mod_authn_socache

User is affected if Apache version is 2.4.0 to 2.4.66 AND mod_authn_socache is enabled in a caching forward proxy configuration.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.4.67 or later
Fixed in 2.4.67
Interim mitigation

Upgrade Apache HTTP Server to version 2.4.67 or later. Until upgrade is possible, consider disabling the caching forward proxy configuration or restricting network access to reduce exposure.

Recommended fix High confidence

2.4.67

  1. 1. Back up your current Apache HTTP Server configuration files (httpd.conf, any included config files)
  2. 2. Check your current Apache version using: httpd -v or apache2 -v
  3. 3. Stop the Apache service: systemctl stop httpd (or apache2)
  4. 4. Update your package repository if using a package manager
  5. 5. Install Apache HTTP Server version 2.4.67 or newer
  6. 6. Restore your configuration files from backup if they were overwritten
  7. 7. Verify the new version: httpd -v
  8. 8. Start the Apache service: systemctl start httpd (or apache2)

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in HTTP Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-33007 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data