CVE-2026-82744

Ash.Reactor change step fails open, skipping a change when its where guard raises

LOW
2.1
CVSS Score
Published: September 1, 2026 at 03:39 AM UTC
Updated: September 1, 2026 at 09:31 PM UTC
1 product affected across 1 vendorAsh

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Severity
LOW2.1
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

Not Failing Securely (Failing Open) vulnerability in ash-project ash skips an Ash.Reactor change when the guard controlling it raises, so a change meant to run does not. An Ash.Reactor change step can be gated by where validations that decide whether the change runs. Ash.Reactor.ChangeStep (lib/ash/reactor/steps/change_step.ex) evaluated those guards in apply_where_clauses/3, and apply_validation rescued any exception into {:error, error}. The reduce treated that identically to a guard whose condition was simply not met and bypassed the change. So when a guard raises (for example on attacker-influenced input), a change that enforces a security-relevant modification is skipped rather than failing the step. The fix distinguishes a raised exception (now {:raised, error}) and halts the step with an error, failing closed. This issue affects ash: from 3.0.0-rc.17 before 3.32.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

90%
3.0.0-rc.17 ≤ v < 3.32.23.0.0-rc.17321f43bd05ad9544e693cbf797243693e51a6be4
Vendor states this is fixed in 6d2eb86ea8d2ba5ffac89c1b8b9bf46e331feabc (fixed)
Affected range stops below 3.32.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

2.1LOWEEF
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-636

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