Integer Underflow Affecting lexbor package, versions <3.0.0-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.27% (19th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-LEXBOR-15665437
  • published16 Mar 2026
  • disclosed13 Mar 2026

Introduced: 13 Mar 2026

CVE-2026-29078  (opens in a new tab)
CWE-191  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Debian:unstable lexbor to version 3.0.0-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream lexbor package and not the lexbor package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1