CVE-2026-120456
MediumCVSS 6.1Summary
L-SMASH through 2.14.5 contains a heap out-of-bounds write vulnerability in isom_read_hdlr() and isom_read_dref_entry() in core/read.c triggered by oversized box sizes. Crafted MP4 or MOV files declaring hdlr or url box sizes larger than remaining data stall the stream position and corrupt heap memory.
Risk Assessment
Heap memory corruption may lead to application crashes or potentially code execution. The risk affects applications parsing untrusted MP4/MOV files with L-SMASH.
Recommendation
Update L-SMASH to a version containing the fix. Until then, avoid processing untrusted MP4/MOV files.
Other vulnerabilities in L-SMASH
See all- CVE-2026-110599High
L-SMASH through 2.14.5 contains a double free vulnerability in hevc_setup_first_summary() and h264_setup_first_summary() in importer/nalu_imp.c that frees borrowed codec-specific objects on error paths. Attackers can supply a crafted Annex-B elementary stream lacking a parseable SPS to lsmash_read_file() or the boxdumper, remuxer, or muxer tools, causing use-after-free, heap corruption, and crashes.
- CVE-2016-20099Medium
L-SMASH through 2.14.5 contains an infinite loop vulnerability in vc1_importer_probe() in importer/vc1_imp.c. Attackers can supply a file consisting only of zero bytes, which lsmash_read_file() probes automatically, causing indefinite CPU consumption and denial of service.
Original NVD description (English source)
L-SMASH through 2.14.5 contains a heap out-of-bounds write vulnerability in isom_read_hdlr() and isom_read_dref_entry() in core/read.c triggered by oversized box sizes. Attackers can supply crafted MP4 or MOV files declaring hdlr or url box sizes larger than remaining data, stalling the stream position and corrupting heap memory to crash applications.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS