Skip to content
Fencer Vulns
high 8.2

CVE-2023-45811 json

Prototype pollution vulnerability leading to arbitrary code execution in synchrony deobfuscator

published 2023-10-17 3 y ago modified 2026-06-17 4 mo ago also GHSA-jg82-xh3w-rhxx , EUVD-2023-2761

cvss
8.2
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits
0
none known

Summary

Synchrony deobfuscator is a javascript cleaner & deobfuscator. A `__proto__` pollution vulnerability exists in versions before v2.4.4. Successful exploitation could lead to arbitrary code execution. A `__proto__` pollution vulnerability exists in the `LiteralMap` transformer allowing crafted input to modify properties in the Object prototype. A fix has been released in `deobfuscator@2.4.4`. Users are advised to upgrade. Users unable to upgrade should launch node with the [--disable-proto=delete][disable-proto] or [--disable-proto=throw][disable-proto] flags

Patch / fix

  • npm deobfuscator 2.4.4
  • relative synchrony 2.4.4

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
2 y ago

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/relative/synchrony/security/advisories/GHSA-jg82-xh3w-rhxx referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.2 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
GitHub 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
npm deobfuscator
>=2.0.1, <2.4.4
2.4.4

Affected products

  • relative synchrony

Classification

Weakness
  • CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.