CVE-2010-4344

Out-of-bounds Write in Heap-based buffer overflow in the string_vformat function in string

Verified by Precogs Threat Research
Last Updated: Apr 21, 2026
Base Score
9.8CRITICAL

Executive Summary

CVE-2010-4344 is a critical severity vulnerability affecting binary-analysis. It is classified as Out-of-bounds Write. This vulnerability is actively being exploited in the wild.

Precogs AI Insight

"The primary vulnerability vector is rooted in within Buffer overflow in the string_vformat function in string., allowing the insecure processing of malicious payloads. If successfully exploited, a malicious user could gain unauthorized read or write access, effectively hijacking underlying configurations. The Precogs Binary SAST engine detects such memory corruption vulnerabilities to intercept unsafe execution patterns."

Exploit Probability (EPSS)
High (53.1%)
Public POC
Available
Exploit Probability
High (84%)
Public POC
Actively Exploited
Affected Assets
binary analysisCWE-787

What is this vulnerability?

CVE-2010-4344 is categorized as a critical Out-of-bounds Write flaw with a CVSS base score of 9.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session that includes two MAIL commands in conjunction with a large message containing crafted headers, leading to improper rejection logging.

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 Score9.8 (CRITICAL)
Vector StringCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
PublishedDecember 14, 2010
Last ModifiedApril 21, 2026
Related CWEsCWE-787, CWE-787

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-2010-4344

  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

Precogs Binary SAST/DAST engine performs deep structural analysis of compiled binaries, detecting memory corruption, control-flow hijacking, and privilege escalation vulnerabilities without requiring source code access.

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
SourceNetwork packet or file input
VectorData exceeds the allocated buffer bounds during a copy operation
Sinkstrcpy(), memcpy(), or pointer arithmetic
ImpactMemory corruption, Remote Code Execution (RCE)

Vulnerable Code Pattern

// ❌ VULNERABLE: Out-of-bounds write
void process_data(char *input) {
    char buffer[64];
    // Taint sink: copies without bounds checking
    strcpy(buffer, input);
}

Secure Code Pattern

// ✅ SECURE: Bounded copy
void process_data(char *input) {
    char buffer[64];
    // Sanitized boundary check
    strncpy(buffer, input, sizeof(buffer) - 1);
    buffer[sizeof(buffer) - 1] = '\0';
}

How Precogs Detects This

Precogs Binary SAST engine explicitly uncovers memory boundary violations and unsafe memory management functions in compiled binaries.\n

Related Vulnerabilitiesvia CWE-787

Is your system affected?

Precogs AI detects CVE-2010-4344 in compiled binaries, LLMs, and application layers — even without source code access.