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Fencer Intel
low 3.3

CVE-2026-3387 json

wren-lang wren wren_compiler.c getByteCountForArguments null pointer dereference

published 8mo ago modified 4mo ago also EUVD-2026-9122

cvss
3.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits
0
none known

Summary

A vulnerability has been found in wren-lang wren up to 0.4.0. Affected by this issue is the function getByteCountForArguments of the file src/vm/wren_compiler.c. Such manipulation leads to null pointer dereference. Local access is required to approach this attack. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
8mo ago

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/oneafter/0122/blob/main/i1220/repro referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/wren-lang/wren/issues/1220 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 4.8 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
CNA 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
CNA 3.0 3.3 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
CNA 2.0 1.7 AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:ND/RC:UR
CNA 4.0 1.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA 2.0 1.7 AV:L/AC:L/Au:S/C:N/I:N/A:P

Affected products

  • wren-lang wren

Classification

Weakness
  • CWE-476 NULL Pointer Dereference
  • CWE-404 Improper Resource Shutdown or Release

References

Sources

Fencer Intel 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.