CVE-2019-0211

Use After Free in In Apache HTTP Server 2

Verified by Precogs Threat Research
Last Updated: Oct 27, 2025
Base Score
7.8HIGH

Executive Summary

CVE-2019-0211 is a high severity vulnerability affecting binary-analysis. It is classified as Use After Free. This vulnerability is actively being exploited in the wild.

Precogs AI Insight

"Apache HTTP Server fails to properly manage memory boundaries within shared scoreboards. Attackers exploit this by sending a crafted request to a worker process to manipulate shared memory and elevate privileges to root (CARPE DIEM). Precogs Binary SAST engine identifies insecure IPC memory boundary checks."

Exploit Probability (EPSS)
High (90.9%)
Public POC
Available
Exploit Probability
Elevated (52%)
Public POC
Actively Exploited
Affected Assets
binary analysisCWE-416

What is this vulnerability?

CVE-2019-0211 is categorized as a high Use After Free flaw with a CVSS base score of 7.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

In Apache HTTP Server 2.4 releases 2.4.17 to 2.4.38, with MPM event, worker or prefork, code executing in less-privileged child processes or threads (including scripts executed by an in-process scripting interpreter) could execute arbitrary code with the privileges of the parent process (usually root) by manipulating the scoreboard. Non-Unix systems are not affected.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

MetricValue
CVSS Base Score7.8 (HIGH)
Vector StringCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
PublishedApril 8, 2019
Last ModifiedOctober 27, 2025
Related CWEsCWE-416, CWE-416

Impact on Systems

Remote Code Execution: Attackers can overwrite the instruction pointer to redirect execution to malicious shellcode.

Memory Corruption: Overwriting adjacent memory regions can corrupt critical application state, leading to privilege escalation.

Denial of Service: Triggering segmentation faults results in immediate disruption of critical systems.

How to Fix and Mitigate CVE-2019-0211

  1. Apply Vendor Patches Immediately: This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog. Apply updates per vendor instructions.
  2. Verify Patch Deployment: Confirm all instances are updated using Precogs continuous monitoring.
  3. Review Audit Logs: Investigate historical access logs for indicators of compromise related to this attack surface.
  4. Implement Defense-in-Depth: Deploy WAF rules, network segmentation, and endpoint detection to limit blast radius.

Defending with Precogs AI

Apache HTTP Server fails to properly manage memory boundaries within shared scoreboards. Attackers exploit this by sending a crafted request to a worker process to manipulate shared memory and elevate privileges to root (CARPE DIEM). Precogs Binary SAST engine identifies insecure IPC memory boundary checks.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

StageDetail
SourceMemory allocation pointer
VectorPointer is accessed after the memory has been freed
SinkDangling pointer dereference
ImpactMemory corruption, sandbox escape, Remote Code Execution (RCE)

Vulnerable Code Pattern

// ❌ VULNERABLE: Use After Free
char *ptr = malloc(256);
free(ptr);
// Taint sink: accessing freed memory
strcpy(ptr, "Exploit payload");

Secure Code Pattern

// ✅ SECURE: Nullifying pointers
char *ptr = malloc(256);
free(ptr);
// Sanitized state: pointer set to NULL
ptr = NULL;

How Precogs Detects This

Precogs Binary SAST engine identifies dangling pointers and complex use-after-free conditions in compiled rendering engines and system libraries.\n

Related Vulnerabilitiesvia CWE-416

Is your system affected?

Precogs AI detects CVE-2019-0211 in compiled binaries, LLMs, and application layers — even without source code access.