CVE-2026-120456 (GCVE-0-2026-120456)
Vulnerability from cvelistv5 – Published: 2026-11-02 14:29 – Updated: 2026-11-02 17:31
VLAI
EPSS
VEX
Title
L-SMASH through 2.14.5 Heap Out-of-Bounds Write via hdlr and url Boxes
Summary
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.
Severity
6.1 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-02 17:04 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://github.com/l-smash/l-smash/issues/112 | issue-tracking |
| https://github.com/l-smash/l-smash/commit/805ee3c… | patch |
| https://github.com/l-smash/l-smash/blob/v2.14.5/c… | technical-description |
| https://github.com/l-smash/l-smash/blob/v2.14.5/c… | technical-description |
| https://hackmd.io/@haindpwn/lsmash-hdlr-dref-box-… | technical-description |
| https://www.vulncheck.com/advisories/l-smash-thro… | third-party-advisory |
Impacted products
Date Public
2026-10-22 00:00
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Nomenclature
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