CVE-2026-104026 Command injection in Sapling SCM
Attackers can execute arbitrary code on victims by crafting Git subtree URLs with control characters in Sapling SCM repositories.
- 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-2026-104026?
CVE-2026-104026 is a high-severity command injection vulnerability in Meta Platforms, Inc Sapling SCM, published on 2 Oct 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
In Sapling SCM prior to v0.2.20260929-102736, control characters were allowed to be embedded in Git subtree URLs. A maliciously constructed repository, if cloned by a target, could trigger code execution on otherwise read-only actions such as sl log/blame/annotate.
Weakness: CWE-150
Which versions are affected by CVE-2026-104026?
How do I fix CVE-2026-104026?
No fix has been published for CVE-2026-104026 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-104026 being exploited?
There is no known exploitation of CVE-2026-104026 in the wild and no public exploit code.
Sources
Also known as GHSA-g4x4-gm4c-5r8h.