CVE-2019-19203

HIGH

Oniguruma 6.x <6.9.4_rc2 - Memory Corruption

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2019-19203. PoCs published by ManhNDd, tarantula-team.

AI-analyzed exploit summary This repository contains a functional proof-of-concept exploit for CVE-2019-19203, demonstrating a heap-based buffer over-read vulnerability in Oniguruma's gb18030_mbc_enc_len function. The PoC includes a C program that triggers the vulnerability, along with a detailed crash log and root cause analysis.

Description

An issue was discovered in Oniguruma 6.x before 6.9.4_rc2. In the function gb18030_mbc_enc_len in file gb18030.c, a UChar pointer is dereferenced without checking if it passed the end of the matched string. This leads to a heap-based buffer over-read.

Exploits (2)

nomisec WORKING POC 3 stars
by ManhNDd · poc
https://github.com/ManhNDd/CVE-2019-19203

This repository contains a functional proof-of-concept exploit for CVE-2019-19203, demonstrating a heap-based buffer over-read vulnerability in Oniguruma's gb18030_mbc_enc_len function. The PoC includes a C program that triggers the vulnerability, along with a detailed crash log and root cause analysis.

Classification
Working Poc 100%
Attack Type
Dos
Complexity
Moderate
Reliability
Reliable
Target: Oniguruma 6.x before 6.9.4_rc2
No auth needed
Prerequisites: Oniguruma library compiled with AddressSanitizer
devstral-2 · analyzed Feb 19, 2026 Full analysis →
nomisec WORKING POC
by tarantula-team · poc
https://github.com/tarantula-team/CVE-2019-19203

This repository contains a functional proof-of-concept exploit for CVE-2019-19203, demonstrating a heap-based buffer over-read vulnerability in Oniguruma's gb18030_mbc_enc_len function. The PoC includes a C program that triggers the vulnerability using a crafted input string, along with a detailed crash log from AddressSanitizer.

Classification
Working Poc 100%
Attack Type
Dos
Complexity
Moderate
Reliability
Reliable
Target: Oniguruma 6.x before 6.9.4_rc2
No auth needed
Prerequisites: Oniguruma library compiled with AddressSanitizer
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (6)

Core 6
Core References
Exploit, Patch, Third Party Advisory x_refsource_misc
https://github.com/kkos/oniguruma/issues/163
Exploit, Third Party Advisory x_refsource_misc
https://github.com/ManhNDd/CVE-2019-19203
Third Party Advisory x_refsource_misc
https://github.com/tarantula-team/CVE-2019-19203

Scores

CVSS v3 7.5
EPSS 0.0405
EPSS Percentile 89.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-125
Status published
Products (4)
fedoraproject/fedora 30
fedoraproject/fedora 31
oniguruma_project/oniguruma 6.9.4 rc1
oniguruma_project/oniguruma 6.0.0 - 6.9.4
Published Nov 21, 2019
Tracked Since Feb 18, 2026