Vulnerabilities

Vulnerability · CVE-1999-1199

Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, a…

Published Aug 7, 1998 · catalog updated Jun 16, 2026 · http server

Last checked Nov 4, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-1999-1199. EPSS is 7.58%. Act only if a listed version of http server is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
Critical10.0
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
7.58%
Remediation
Version ranges on file
Affected products
cpe apache/http server

Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, aka the "sioux" vulnerability.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe apache/http server<= 1.3.1

How to fix CVE-1999-1199

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-1999-1199. EPSS is 7.58%. Act only if a listed version of http server is installed.

Which versions are affected?

Compare what you have installed with apache/http server <= 1.3.1. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 7.58%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Technology hubs

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 7, 1998 · Monitored products — critical

    Detected

    Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, aka the "sioux" vulnerability.

  2. Jun 16, 2026 · Monitored products — critical

    Updated

    Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, aka the "sioux" vulnerability.

Sources

  • CVE.orgVulnerability recordCVE-1999-1199

    Official CVE identifier

    cve.org
  • Monitored products — criticalVendor advisoryCVE-1999-1199

    Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, aka the "sioux" vulnerability.

    nvd.nist.gov

References

Freshness

Last verified in this catalog Nov 3, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • CVE.orgNov 4, 2026
  • Monitored products — criticalNov 3, 2026