CVE-2026-29078
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.
Published:Mar 13, 2026
Last Modified:Mar 24, 2026
EPS:Mar 13, 2026
EPSS Score:0.00055
CVSS Score:7.5
Affected Products
Vendor
Product
Action
Vendor
Lexbor
Product
Lexbor
Lexbor
Lexbor
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
No CAPEC recorded yet
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
