CVE-2026-82735
Match regex runs on over-length input in Ash.Type.String, enabling regex denial of service
Published Sep 1, 2026
CVSS 4.0 · 5.9 Medium
EPSS < 1%
KEV · Not listed
Description
Uncontrolled Resource Consumption vulnerability in ash-project ash allows an attacker to force an expensive regular expression to run on input that a length constraint should have already rejected.
Ash.Type.String.apply_constraints/2 (lib/ash/type/string.ex) evaluated the :match regex regardless of the min_length and max_length constraints on the same attribute. Because the length check did not gate the regex, an over-length value that the length constraint rejects still had the pattern applied to it, so the length limit that would otherwise bound the work never constrained the regex input. Against a backtracking pattern this yields catastrophic regex evaluation on attacker-sized input, and even a linear pattern runs on arbitrarily large input, consuming CPU per request. The fix skips the :match regex whenever a length constraint is violated, making the two checks order-independent.
This issue affects ash: from 0.10.0 before 3.32.2.
Ash.Type.String.apply_constraints/2 (lib/ash/type/string.ex) evaluated the :match regex regardless of the min_length and max_length constraints on the same attribute. Because the length check did not gate the regex, an over-length value that the length constraint rejects still had the pattern applied to it, so the length limit that would otherwise bound the work never constrained the regex input. Against a backtracking pattern this yields catastrophic regex evaluation on attacker-sized input, and even a linear pattern runs on arbitrarily large input, consuming CPU per request. The fix skips the :match regex whenever a length constraint is violated, making the two checks order-independent.
This issue affects ash: from 0.10.0 before 3.32.2.
Affected Products
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CVE record
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NVD configurations
No data
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Red Hat packages
No data
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OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
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| ash-project | ash | unaffected |
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| ash-project | ash | unaffected |
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No data.
No data.
| Vendor | Product | Versions | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ash-project | Ash |
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| Ash-project | Ash |
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| Ash-project | Ash |
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Remediation
Tracking
Advisories
Metrics
Attack Vector Local
Attack Complexity Low
Privileges Required None
Attack Requirements Present
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
No CVSS v3.1
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.180% probability within 30 days)
Exploitation poc
Automatable no
Technical Impact partial
References
History
Sep 1, 2026 2:30 PM
Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
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| Metrics |
ssvc
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Sep 1, 2026 3:30 AM
Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Uncontrolled Resource Consumption vulnerability in ash-project ash allows an attacker to force an expensive regular expression to run on input that a length constraint should have already rejected. Ash.Type.String.apply_constraints/2 (lib/ash/type/string.ex) evaluated the :match regex regardless of the min_length and max_length constraints on the same attribute. Because the length check did not gate the regex, an over-length value that the length constraint rejects still had the pattern applied to it, so the length limit that would otherwise bound the work never constrained the regex input. Against a backtracking pattern this yields catastrophic regex evaluation on attacker-sized input, and even a linear pattern runs on arbitrarily large input, consuming CPU per request. The fix skips the :match regex whenever a length constraint is violated, making the two checks order-independent. This issue affects ash: from 0.10.0 before 3.32.2. | |
| Title | Match regex runs on over-length input in Ash.Type.String, enabling regex denial of service | |
| First Time appeared |
Ash-project
Ash-project ash |
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| Weaknesses | CWE-400 | |
| CPEs | cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Ash-project
Ash-project ash |
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| References |
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| Metrics |
cvssV4_0
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Subscriptions
Weaknesses