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CVE Record

CVE-2019-19203: An issue was discovered in Oniguruma 6.x before 6.9.4_rc2.

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.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

Oniguruma, a regular-expression library embedded in many software stacks, can read past a heap buffer when handling GB18030 encoded input. The provided sources do not give CVSS, proven impact beyond over-read, or active exploitation evidence.

Executive priority

Prioritize remediation as dependency risk rather than emergency incident response unless local exposure includes untrusted regex or encoded text processing in critical services.

Technical view

CVE-2019-19203 affects Oniguruma 6.x before 6.9.4_rc2. In gb18030_mbc_enc_len in gb18030.c, a UChar pointer may be dereferenced after passing the matched string end, causing a heap-based buffer over-read.

Likely exposure

Exposure is most likely where applications or packaged software embed vulnerable Oniguruma 6.x and process GB18030 encoded regular-expression input from untrusted or semi-trusted sources.

Exploitation context

The bundle marks KEV as false and provides no cited evidence of active exploitation. Public GitHub references exist, so defenders should assume technical details may be accessible.

Researcher notes

Evidence is limited to the CVE description, Oniguruma release and issue references, public GitHub references, and Fedora package advisories. Impact should not be expanded beyond heap over-read without product-specific analysis.

Mitigation direction

  • Upgrade Oniguruma to 6.9.4_rc2 or a later vendor-supported fixed release.
  • Apply relevant operating-system package updates, including Fedora advisories where applicable.
  • Identify software that statically bundles Oniguruma and rebuild it against a fixed version.
  • Check upstream vendor guidance for products embedding Oniguruma before choosing compensating controls.

Validation and detection

  • Inventory direct and transitive use of Oniguruma across packages, containers, and source builds.
  • Confirm deployed Oniguruma versions are not 6.x before 6.9.4_rc2.
  • Review applications that accept untrusted regex patterns or GB18030 encoded content.
  • Verify vendor package changelogs or advisories show CVE-2019-19203 remediation.
Prepared
Confidence
medium
Sources
8

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2019-19203 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
7Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

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