CVE-2026-77856
Unbounded atom creation in ash_typescript enables remote DoS by exhausting the BEAM atom table.
Is CVE-2026-77856 being exploited?
Not confirmed. CVE-2026-77856 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.32% probability of exploitation in the next 30 days.
How severe is CVE-2026-77856?
CVE-2026-77856 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-77856?
Yes. A fix has been recorded for CVE-2026-77856. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-77856 affect?
CVE-2026-77856 affects ash-project/ash_typescript >=0.11.0 <0.18.0, Elixir/Erlang (BEAM) nodes using ash_typescript. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-77856?
Upgrade ash_typescript to >=0.18.0; validate/limit client field names; restrict untrusted access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated attacker can mint many permanent atoms via crafted field names, exhausting BEAM atom table and aborting the node (remote DoS).
Immediate action required
- affected>= 0.11.0 and < 0.18.0
- affected>= 7c3d30896f2f9a54edea17e3787549776b1b288d and < 0ab5c83a7df28d51a6de1fb9b859a142b2b12919
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.