Vulnerability · Published Oct 14, 2026 · Assigned by VulnCheck

CVE-2026-110599L-SMASH through 2.14.5 Double Free in HEVC and H.264 Importer Probe

High 7.1

In plain English

A high-severity double free in l-smash from l-smash. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities).

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.2%top 84.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
l-smash	l-smash	0 – through 2.14.5

Weakness: CWE-415 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H

References

https://hackmd.io/@haind-pwn/l-smash-hevc-importer-double-free third-party-advisory
https://github.com/l-smash/l-smash/blob/v2.14.5/importer/nalu_imp.c#L1356-L1378 technical-description
https://github.com/l-smash/l-smash/blob/v2.14.5/importer/nalu_imp.c#L697-L715 technical-description
VulnCheck Advisory: L-SMASH through 2.14.5 Double Free in HEVC and H.264 Importer Probe third-party-advisory
https://hackmd.io/@haind-pwn/cve-2016-20099-2026-110599-l-smash-hevc-importer-double-free exploit