Is there a public exploit for CVE-2026-120456?

No public exploit for CVE-2026-120456 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-120456?

CVE-2026-120456 scores CVSS 6.9 (v4.0), rated medium.

What does CVE-2026-120456 affect?

CVE-2026-120456 affects l-smash l-smash.

6.9 Medium

L-SMASH through 2.14.5 contains a heap out-of-bounds write vulnerability in isomreadhdlr() and isomreaddrefentry() in core/read.c triggered…

CVE-2026-120456

L-SMASH through 2.14.5 contains a heap out-of-bounds write vulnerability in isomreadhdlr() and isomreaddrefentry() 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.

Assessment

CVSS: 6.9 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 2 November 2026
Last updated: 2 November 2026
Affected: l-smash · l-smash
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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