Critical

Prototype Pollution in CASL Ability (@casl/ability) 2.4.0-6.7.4

IdentifiersCVE-2026-1774CWE-1321

CASL Ability (npm package @casl/ability) versions 2.4.0 through 6.7.4 contain a prototype pollution vulnerability. The issue allows attacker-controlled properties to be introduced into JavaScript object prototypes (e.g., via dangerous keys such as proto/constructor/prototype) through affected CASL Ability API usage patterns, potentially altering application behavior that relies on object property lookups.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Prototype pollution can enable manipulation of application object prototypes, which may result in application logic bypass and denial of service, and in some cases may be escalated to code execution depending on how the polluted properties are subsequently used by the consuming application.

Mitigation

If you can’t patch tonight, do this now.

Ensure untrusted input is not used to construct, merge, or otherwise supply objects into CASL Ability APIs in vulnerable code paths. Filter/strip dangerous keys ("proto", "prototype", "constructor") from user-controlled JSON/objects, and avoid generic deep-merge utilities on untrusted data in the same flows until the package can be upgraded.

Remediation

Patch, then assume compromise.

Upgrade @casl/ability to version 6.7.5 or later, which contains the fix.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

1 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

1 SOURCESView more in app

the hacker newsNews

Feb 16, 2026

Weekly Recap: Outlook Add-Ins Hijack, 0-Day Patches, Wormable Botnet & AI Malware

Unknown (listed as a trending CVE for CASL Ability without details in the provided content).

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity