Description
HarfBuzz from 8.0.0 through 14.6.0 contains a NULL pointer dereference vulnerability in the experimental WebAssembly shaper host imports buffer_set_contents, face_create, and font_set_coords. Attackers can supply a crafted font whose embedded wasm module passes out-of-range addresses with non-zero lengths, crashing any application that shapes text with the font.
References6
- github.com/harfbuzz/harfbuzz/blob/14.6.0/src/hb-wasm-api-buffer…
- github.com/harfbuzz/harfbuzz/blob/14.6.0/src/hb-wasm-api-face.h…
- github.com/harfbuzz/harfbuzz/blob/14.6.0/src/hb-wasm-api-font.h…
- github.com/harfbuzz/harfbuzz/commit/a71aa86c2bac114fafb6b47f8da…
- github.com/harfbuzz/harfbuzz/pull/6414
- www.vulncheck.com/advisories/harfbuzz-8.0.0-through-14.6.0-weba…
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - CVSS 4.0
-
6.8
MEDIUM
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 6 · as of 9 November 2026
- CWE
- CWE-476
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.