Apache2: A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header…
A vulnerability in Apache HTTP Server versions 2.4.54 and earlier allows a carefully crafted If: request header to cause a memory read or write of a single zero byte beyond the header value in heap memory. This memory corruption can lead to a process crash. The issue affects multiple specific Ubuntu package versions of Apache 2.4. No known exploits in the wild have been reported.
AI Analysis
Technical Summary
This vulnerability involves improper handling of the If: request header in Apache HTTP Server 2.4.54 and earlier, where a carefully crafted header can cause an out-of-bounds memory read or a write of a zero byte in heap memory beyond the header value. This memory corruption can cause the Apache process to crash, resulting in a denial of service. The vulnerability affects numerous Ubuntu-specific Apache 2.4 package versions as listed. There is no indication of confidentiality or integrity impact, only availability impact due to potential crashes.
Potential Impact
The primary impact is denial of service caused by process crashes when processing malicious If: headers. There is no evidence of information disclosure or privilege escalation. The vulnerability does not require authentication and can be triggered remotely by sending crafted HTTP requests.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a patch is applied, consider restricting or filtering suspicious If: headers at perimeter controls if feasible. Monitor for updates from Apache and Ubuntu regarding official fixes.
Apache2: A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header…
Description
A vulnerability in Apache HTTP Server versions 2.4.54 and earlier allows a carefully crafted If: request header to cause a memory read or write of a single zero byte beyond the header value in heap memory. This memory corruption can lead to a process crash. The issue affects multiple specific Ubuntu package versions of Apache 2.4. No known exploits in the wild have been reported.
CVSS v3.1
Score 7.5high
Affected software
pkg:deb/ubuntu/[email protected]+esm15?arch=source&distro=esm-infra-legacy/trustypkg:deb/ubuntu/[email protected]+esm8?arch=source&distro=esm-infra/xenialpkg:deb/ubuntu/[email protected]?arch=source&distro=bionicpkg:deb/ubuntu/[email protected]?arch=source&distro=focalpkg:deb/ubuntu/[email protected]?arch=source&distro=jammyRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves improper handling of the If: request header in Apache HTTP Server 2.4.54 and earlier, where a carefully crafted header can cause an out-of-bounds memory read or a write of a zero byte in heap memory beyond the header value. This memory corruption can cause the Apache process to crash, resulting in a denial of service. The vulnerability affects numerous Ubuntu-specific Apache 2.4 package versions as listed. There is no indication of confidentiality or integrity impact, only availability impact due to potential crashes.
Potential Impact
The primary impact is denial of service caused by process crashes when processing malicious If: headers. There is no evidence of information disclosure or privilege escalation. The vulnerability does not require authentication and can be triggered remotely by sending crafted HTTP requests.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a patch is applied, consider restricting or filtering suspicious If: headers at perimeter controls if feasible. Monitor for updates from Apache and Ubuntu regarding official fixes.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2006-20001
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:14.04:LTS","Ubuntu:Pro:16.04:LTS","Ubuntu:18.04:LTS","Ubuntu:20.04:LTS","Ubuntu:22.04:LTS"]
- Cvss Version
- 3.1
Threat ID: 6a6151309c2644c7f8da7297
Added to database: 07/22/2026, 23:24:32 UTC
Last enriched: 07/23/2026, 00:09:15 UTC
Last updated: 09/10/2026, 19:36:45 UTC
Views: 41
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