How severe is CVE-2025-65570?

CVE-2025-65570 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-65570 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-65570?

CVE-2025-65570 affects Jsish. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-65570?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-65570 have an EU (EUVD) identifier?

Yes. CVE-2025-65570 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205581.

When was CVE-2025-65570 published?

CVE-2025-65570 was published on 2025-12-29 and last updated on 2026-06-17.

CVE-2025-65570

CVE-2025-65570 is a critical-severity vulnerability in Jsish with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-843.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-205581
Weakness: CWE-843
Affected product: Jsish
Published: 2025-12-29
Last modified: 2026-06-17

Description

A type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode. When an “instanceof” expression uses an array element access as the left-hand operand inside a for-in loop, the instructions implementation leaves an additional array reference on the stack rather than consuming it during OP_INSTANCEOF. As a result, OP_NEXT interprets the array as an iterator object and reads the iterCmd function pointer from an invalid structure, potentially causing a crash or enabling code execution depending on heap layout.

Frequently asked questions

What is CVE-2025-65570?: A type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode. When an “instanceof” expression uses an array element access as the left-hand operand inside a for-in loop, the instructions implementation leaves an additional array reference on the stack rather than consuming it during OP_INSTANCEOF. As a result, OP_NEXT interprets the array as an iterator object and reads the iterCmd function pointer from an invalid structure, potentially causing a crash or enabling code execution depending on heap layout.
How severe is CVE-2025-65570?: CVE-2025-65570 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-65570 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-65570?: CVE-2025-65570 affects Jsish. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-65570?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-65570 have an EU (EUVD) identifier?: Yes. CVE-2025-65570 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205581.
When was CVE-2025-65570 published?: CVE-2025-65570 was published on 2025-12-29 and last updated on 2026-06-17.

References

https://blog.mcsky.ro/writeups/2025/11/15/inline8-writeup.html

Affected products (1)

cpe:2.3:a:jsish:jsish:2.0:*:*:*:*:*:*:*

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