Vulnerability · Published Oct 18, 2026 · Assigned by VulnCheck
CVE-2026-112007Schism Tracker through 20260524 Heap Out-of-Bounds Write via ULT Loader
Medium 6.1
In plain English
A medium-severity out-of-bounds write in Schism Tracker from schismtracker. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities).
Severity (CVSS 3.1)6.1Medium
Exploit odds (30 days)0.1%top 97.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
Schism Tracker through 20260524 contains a heap out-of-bounds write vulnerability in fmt_ult_load_song() in fmt/ult.c that fails to clamp the one-byte sample count to MAX_SAMPLES. Attackers can supply a crafted .ult module that overwrites the instruments pointer array, causing csf_destroy() to free attacker-chosen pointers and crash the application.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | schism | no fix listed | DEBIAN-CVE-2026-112007 |
| Debian:13 | schism | no fix listed | DEBIAN-CVE-2026-112007 |
| Ubuntu:22.04:LTS | schism | no fix listed | UBUNTU-CVE-2026-112007 |
| Ubuntu:24.04:LTS | schism | no fix listed | UBUNTU-CVE-2026-112007 |
| Ubuntu:26.04:LTS | schism | no fix listed | UBUNTU-CVE-2026-112007 |
| Ubuntu:26.10 | schism | no fix listed | UBUNTU-CVE-2026-112007 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| schismtracker | Schism Tracker | 0 – through 20260524 |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
References
- https://hackmd.io/@haindpwn/schismtracker-ult-sample-count-oob-write technical-description, exploit
- https://github.com/schismtracker/schismtracker/blob/74215ae300b555928332e03152dfcdc898f96ca6/fmt/ult.c#L319-L330 technical-description
- https://github.com/schismtracker/schismtracker product
- VulnCheck Advisory: Schism Tracker through 20260524 Heap Out-of-Bounds Write via ULT Loader third-party-advisory