CVE-2026-29078 (GCVE-0-2026-29078)
Vulnerability from cvelistv5 – Published: 2026-03-13 17:18 – Updated: 2026-03-16 17:05
VLAI
EPSS
VEX
Title
Integer Underflow in Lexbor ISO‑2022‑JP Encoder
Summary
Lexbor is a web browser engine library. Prior to 2.7.0, the ISO‑2022‑JP encoder in Lexbor fails to reset the temporary size variable between iterations. The statement ctx->buffer_used -= size with a stale size = 3 causes an integer underflow that wraps to SIZE_MAX. Afterwards, memcpy is called with a negative length, leading to an out‑of‑bounds read from the stack and an out‑of‑bounds write to the heap. The source data is partially controllable via the contents of the DOM tree. This vulnerability is fixed in 2.7.0.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-16 17:05 UTC
Assigner
GitHub_M
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/lexbor/lexbor/security/advisor… | x_refsource_CONFIRM |
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Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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