CVE-2026-45137 Anchor: Program<'info, System> is not properly validated
Attackers can bypass system program validation in Solana Anchor programs, enabling arbitrary cross-program invocations and payment bypasses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45137?
CVE-2026-45137 is a high-severity missing authorization vulnerability in solana-foundation anchor, published on 27 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Anchor is a framework providing several convenient developer tools for writing Solana programs. From 1.0.0 to before 1.0.2, an logic error causes anchor programs to accept any program id when requiring the system program id, causing false assumptions resulting in potential arbitrary cpi in programs that invoke system program instructions. In the TryFrom<&'a AccountInfo<'a>> implementation for Program<'a, T>, the id of T is compared with Pubkey::default() to check whether anchor should allow any executable account, or a specific account, because when no T is supplied, T defaults to (), which implements Id::id() by returning Pubkey::default(). This results in T = () and T = System (which has Pubkey::default() as the id) having the same behavior, both allow any executable account. Programs built with anchor assume that the anchor runtime verifies passed in programs of type Program<'a, System> are in fact the system program. This false assumption can lead to arbitrary CPI or payment bypassing when programs try making CPI calls to the system program using the passed in system program due to the fact that the attacker can pass in any program instead of the system program. This vulnerability is fixed in 1.0.2.
Weakness: CWE-20
Which versions are affected by CVE-2026-45137?
3 open source packages ship an affected version, including anchor-lang. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
anchor-lang crates.io | From 1.0.0 | 1.0.2 |
anchor-lang crates.io | From 1.0.0 | 1.0.2 |
anchor-lang crates.io | From 1.0.0 | 1.0.2 |
Products include Anchor-Lang Anchor.
How do I fix CVE-2026-45137?
Upgrade anchor-lang to 1.0.2 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-45137 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45137 exists.
Sources
Also known as GHSA-c6rc-8jpp-2fgc, RUSTSEC-2026-0144.