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The CVE-2025-26308 vulnerability is a memory leak in the `parseSWF_FILTERLIST` function within `util/parser.c` of libming v0.4.8. When parsing a specially crafted SWF file, the function fails to release allocated memory properly, leading to resource exhaustion and potential denial of service (DoS). Attackers can exploit this flaw by submitting a malicious SWF file, causing the application to consume increasing amounts of memory until it crashes or becomes unresponsive.
The issue stems from improper handling of filter list data structures during SWF parsing. Each time a corrupted SWF file is processed, memory allocations accumulate without being freed, degrading system performance. The vulnerability is classified as medium severity due to its limited impact scope (DoS rather than remote code execution).
DailyCVE Form:
Platform: libming
Version: 0.4.8
Vulnerability: Memory leak
Severity: Medium
Date: 2025-02-20
What Undercode Say:
Exploitation:
- Craft a malicious SWF file with malformed filter list data.
- Trigger parsing via applications using libming (e.g., SWF viewers).
3. Observe memory consumption spikes leading to crash.
Detection & Protection:
1. Patch: Upgrade to libming >= 0.4.9.
2. Sanitization: Reject malformed SWF files before parsing.
- Monitoring: Track memory usage in processes using libming.
Commands & Code:
- Check libming version:
ming-config --version
- Valgrind memory leak check:
valgrind --leak-check=full ./swf_parser malicious.swf
- Sample vulnerable code (parser.c):
void parseSWF_FILTERLIST(SWF swf) { FilterList filters = malloc(sizeof(FilterList)); // Leaked if not freed // ... parsing logic without free() } - Mitigation patch:
</li> <li>free(filters); // Add cleanup
- Exploit PoC (Python):
with open("exploit.swf", "wb") as f: f.write(b"\x46\x57\x53" + b"\xFF" 1000) Corrupted SWF header - System hardening:
ulimit -v 500000 Limit virtual memory per process
- Network protection:
iptables -A INPUT -p tcp --dport 80 -m string --string "SWF" --algo bm -j DROP
- Log analysis (grep for crashes):
journalctl -u apache | grep "out of memory"
- Debugging with gdb:
gdb --args ./swf_parser exploit.swf
- Memory limits (cgroups):
cgcreate -g memory:libming_limit echo 100M > /sys/fs/cgroup/memory/libming_limit/memory.limit_in_bytes
- Static analysis (Clang):
clang --analyze parser.c
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
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