CVE-2026-77856
What it is
Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_typescript allows an unauthenticated attacker to exhaust the BEAM atom table and abort the node via client-supplied typed struct field names. resolve_typed_struct_field/2 in lib/ash_typescript/rpc/field_processing/field_selector.ex looks a client-supplied field name up in the typed struct's reverse map and, when it finds no match, falls back to String.to_atom/1. Because this runs before any field-existence check, an unresolvable name mints a permanent atom rather than being rejected as unknown. Atoms are never garbage collected, so a request carrying many distinct names on a typed struct field grows the atom table until the VM aborts at its limit. This issue affects ash_typescript: from 0.11.0 before 0.18.0.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 8.2 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Weakness
- CWE-770 · Allocation without limits
- Record status
- Deferred
Attack profile CVSS 4.0 · 8.2
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- Present
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-77856.md and follow it. Check whether this project is affected by CVE-2026-77856. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/ash-project/ash_typescript/commit/0ab5c83a7df28d51a6de1fb9b859a142b2b12919
- https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw
- https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw
References
- https://cna.erlef.org/cves/CVE-2026-77856.html
- https://github.com/ash-project/ash_typescript/commit/0ab5c83a7df28d51a6de1fb9b859a142b2b12919
- https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw
- https://osv.dev/vulnerability/EEF-CVE-2026-77856
- https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw