The init_copy function in kernel.c in mruby 1.4.1 makes initialize_copy calls for TT_ICLASS objects, which allows attackers to cause a deni…

published 2018-06-05 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-3762

cvss: 9.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.2%; EPSS 2.2% chance of exploitation in 30 days, percentile 82%
public exploits: 0; none known

The init_copy function in kernel.c in mruby 1.4.1 makes initialize_copy calls for TT_ICLASS objects, which allows attackers to cause a denial of service (mrb_hash_keys uninitialized pointer and application crash) or possibly have unspecified other impact.

Patch / fix

distros 1 links 2

mruby Debian 14, Debian 13, Debian 12 1.4.1+20180622+git640fca32-1

debian advisories DEBIAN-CVE-2018-11743

github.com/mruby/mruby@b64ce17 commit
github.com/mruby/mruby/issues/4027 advisory

Exploit prediction

2.17% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/mruby/mruby/issues/4027 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

CWE-824 Access of Uninitialized Pointer

References

github.com /mruby/mruby/commit/b64ce17852b180dfeea81cf458660be41a78974d
patch, third-party-advisory
github.com /mruby/mruby/issues/4027
exploit, issue-tracking, patch, third-party-advisory
lists.debian.org /debian-lts-announce/2022/05/msg00006.html
mailing-list, third-party-advisory

Sources

CVE List CVE-2018-11743
NVD CVE-2018-11743

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.

Summary