CVE-2025-48431: Apache Thrift Use-After-Free Vulnerability

CVE-2025-48431 Overview

CVE-2025-48431 is a Mismatched Memory Management Routines vulnerability affecting the c_glib language bindings in Apache Thrift. This memory management flaw allows remote attackers to send specially crafted requests that can crash c_glib-based Thrift servers, resulting in a denial of service condition. The vulnerability triggers a "free(): invalid pointer" error, causing a clean but fatal server crash.

Critical Impact

Remote attackers can crash Apache Thrift servers using c_glib bindings without authentication, causing service disruption through specially crafted network requests.

Affected Products

• Apache Thrift versions before 0.23.0
• Apache Thrift c_glib language bindings
• Applications built on c_glib-based Thrift servers

Discovery Timeline

• 2026-04-28 - CVE CVE-2025-48431 published to NVD
• 2026-04-28 - Last updated in NVD database

Technical Details for CVE-2025-48431

Vulnerability Analysis

This vulnerability falls under CWE-762 (Mismatched Memory Management Routines), which occurs when a program uses incompatible memory allocation and deallocation functions. In the context of Apache Thrift's c_glib bindings, the vulnerability stems from memory being allocated using one memory management routine but freed using an incompatible routine.

When a c_glib-based Thrift server processes malformed or specially crafted requests, the memory management mismatch causes the server to attempt freeing a pointer that was not allocated by the corresponding allocation function. This results in the process terminating with an "invalid pointer" error message. The network-accessible nature of this vulnerability means remote attackers can trigger the crash without any prior authentication or special privileges.

Root Cause

The root cause lies in the improper handling of memory within Apache Thrift's c_glib language bindings. The c_glib library uses GLib's memory management functions (g_malloc, g_free, etc.), which must be used consistently. When memory allocated via one method is freed using an incompatible deallocation routine (such as mixing malloc/g_free or g_malloc/free), the underlying memory manager detects the inconsistency and terminates the process to prevent heap corruption. This design flaw in versions prior to 0.23.0 allows attackers to exploit request handling paths that trigger this memory management mismatch.

Attack Vector

The vulnerability is exploitable remotely over the network. An attacker can send specially crafted Thrift protocol requests to a vulnerable c_glib-based server. The server's request parsing or response generation code path contains the mismatched memory management routines, which are triggered when processing the malicious payload. No user interaction or authentication is required to exploit this vulnerability, making it particularly dangerous for internet-facing Thrift services.

The attack does not compromise data confidentiality or integrity; however, the availability impact is significant as the server process crashes immediately upon receiving the malformed request. Attackers can repeatedly exploit this vulnerability to maintain a persistent denial of service condition.

Detection Methods for CVE-2025-48431

Indicators of Compromise

• Server crashes with "free(): invalid pointer" error messages in system logs
• Unexpected process termination of c_glib-based Thrift services
• Spike in failed client connections due to server unavailability
• Core dumps generated from Thrift server processes showing memory deallocation failures

Detection Strategies

• Monitor system logs for "free(): invalid pointer" or similar memory-related error messages from Thrift server processes
• Implement crash monitoring and automatic alerting for c_glib-based Thrift services
• Deploy network traffic analysis to detect anomalous Thrift protocol requests preceding server crashes
• Use application performance monitoring to detect sudden service terminations

Monitoring Recommendations

• Enable detailed logging for Apache Thrift server processes to capture error conditions
• Configure process watchdogs to alert on unexpected Thrift server restarts
• Implement rate limiting on Thrift endpoints to mitigate denial of service impact
• Set up automated health checks to detect service unavailability promptly

How to Mitigate CVE-2025-48431

Immediate Actions Required

• Upgrade Apache Thrift to version 0.23.0 or later immediately
• Identify all applications using Apache Thrift c_glib language bindings in your environment
• Consider temporarily restricting network access to vulnerable Thrift services until patched
• Implement network-level filtering to limit access to Thrift services from trusted sources only

Patch Information

Apache has released version 0.23.0 which addresses this vulnerability by correcting the memory management routine mismatches in the c_glib language bindings. Users are strongly recommended to upgrade to this version or later. For detailed patch information, refer to the Apache Mailing List Thread. Additional technical discussion is available on the Openwall OSS Security Discussion.

Workarounds

• Restrict network access to c_glib-based Thrift servers using firewall rules to allow only trusted clients
• Implement a reverse proxy or load balancer in front of Thrift services to provide basic request filtering
• Deploy process supervisors to automatically restart crashed Thrift services while patches are applied
• Consider temporarily switching to alternative Thrift language bindings if c_glib is not strictly required

# Configuration example - Restrict access to Thrift service port using iptables
iptables -A INPUT -p tcp --dport 9090 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 9090 -j DROP