Security Digest · Vulnerability record
CVE-2026-1774: CASL Ability is Vulnerable to Prototype Pollution
CASL Ability, versions 2.4.0 through 6.7.4, contains a prototype pollution vulnerability.
CVSS 9.8 Critical EPSS 0.7% · p53
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7%, percentile 53: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 53% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
@casl/ability(npm) >= 2.4.0, <= 6.7.4, fixed in 6.7.5. Check your lockfile, including transitive dependencies.
What it is
CASL Ability, versions 2.4.0 through 6.7.4, contains a prototype pollution vulnerability.
From the GitHub advisory
CASL Ability, versions 2.4.0 through 6.7.4, contains a prototype pollution vulnerability.
Weakness type: CWE-1321.
Product: @casl/ability (npm) · Assigned by: certcc · Published: 2026-02-10
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | @casl/ability | >= 2.4.0, <= 6.7.4 | 6.7.5 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| CASL Ability | CASL Ability | 2.4.0 <= 6.7.4 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.71% probability of exploitation activity in the next 30 days; percentile 53.
Timeline
- — CVE record published by certcc
- — GitHub-reviewed advisory GHSA-x9vf-53q3-cvx6 published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-x9vf-53q3-cvx6 github.com
- CVE.org record CVE-2026-1774 cve.org
- NVD entry CVE-2026-1774 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- cwe.mitre.org cwe.mitre.org
- developer.mozilla.org developer.mozilla.org
- kb.cert.org kb.cert.org
- github.com github.com
- github.com github.com