CVE-2021-41751

Buffer overflow via stale Array.slice length

Published Apr 5, 2022 · Updated Aug 4, 2024

Buffer overflow in JerryScript before commit e1ce7dd7271288be8c0c8136eea9107df73a8ce2 allows attackers to trigger memory corruption via Array.slice. The fast-array Array.slice implementation keeps a stale end index when index normalization changes the input length, so element copying reads beyond the valid buffer. Exploitation requires attacker-controlled JavaScript to execute in an embedding application; published records do not establish reliable code execution or exploitation in the wild.

CVSS severity9.8
Critical
EPSS probability1.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in JerryScript before commit e1ce7dd7271288be8c0c8136eea9107df73a8ce2 allows attackers to trigger memory corruption via Array.slice. The fast-array Array.slice implementation keeps a stale end index when index normalization changes the input length, so element copying reads beyond the valid buffer. Exploitation requires attacker-controlled JavaScript to execute in an embedding application; published records do not establish reliable code execution or exploitation in the wild.

The record

CVE
CVE-2021-41751
Published
Apr 5, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Apr 5, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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