CVE-2026-120456

EUVD-2026-115216
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.1 MEDIUM
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://github.com/l-smash/l-smash/blob/v2.14.5/core/read.c#L688-L717
https://github.com/l-smash/l-smash/blob/v2.14.5/core/read.c#L853-L876
https://github.com/l-smash/l-smash/commit/805ee3c9632e054198d3cb5b09c7b7aa36cdd791
https://github.com/l-smash/l-smash/issues/112
https://hackmd.io/@haindpwn/lsmash-hdlr-dref-box-size-oob-write
https://www.vulncheck.com/advisories/l-smash-through-2.14.5-heap-out-of-bounds-write-via-hdlr-and-url-boxes