The CHECK macro in mrbgems/mruby-sprintf/src/sprintf.c in mruby 1.4.1 contains a signed integer overflow, possibly leading to out-of-bounds…

published 2018-07-17 8y ago modified 2026-06-17 4mo ago also EUVD-2018-6259

cvss: 7.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.4%; EPSS 1.4% chance of exploitation in 30 days, percentile 71%
public exploits: 0; none known

The CHECK macro in mrbgems/mruby-sprintf/src/sprintf.c in mruby 1.4.1 contains a signed integer overflow, possibly leading to out-of-bounds memory access because the mrb_str_resize function in string.c does not check for a negative length.

Patch / fix

distros 1

mruby Debian 14, Debian 13, Debian 12 2.0.0-1

debian advisories DEBIAN-CVE-2018-14337

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Exploit prediction

1.35% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

github.com https://github.com/mruby/mruby/issues/4062 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Classification

Weakness

CWE-190 Integer Overflow or Wraparound

References

github.com /mruby/mruby/issues/4062
exploit, issue-tracking, third-party-advisory
lists.debian.org /debian-lts-announce/2022/05/msg00006.html
mailing-list, third-party-advisory

Sources

CVE List CVE-2018-14337
NVD CVE-2018-14337

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