CVE-2026-71266 tinyobjloader-c Stack Buffer Overflow in MTL Material File Line Parsing
A stack buffer overflow in tinyobjloader-c allows attackers to execute arbitrary code or cause denial of service via malicious MTL files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-71266?
CVE-2026-71266 is a high-severity memory corruption vulnerability in syoyo tinyobjloader-c, published on 5 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
tinyobjloader-c's tinyobj_parse_and_index_mtl_file (tinyobj_loader_c.h) reads each line of a .mtl material file into a fixed 4096-byte stack buffer via memcpy(linebuf, p, p_len), guarded only by . The identical vulnerable pattern is duplicated in a second function in the same file.
Weakness: CWE-121
Which versions are affected by CVE-2026-71266?
How do I fix CVE-2026-71266?
No fix has been published for CVE-2026-71266 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-71266 being exploited?
There is no known exploitation of CVE-2026-71266 in the wild and no public exploit code.
Sources
Also known as GHSA-gr59-p4q8-r75g, UBUNTU-CVE-2026-71266.