CVE-2026-113679: harfbuzz · Out-of-bounds Write
Affects harfbuzzSource CVE Database V5
Not known to be exploited · CVSS 7.3 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-20.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 20 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| harfbuzzharfbuzz | Affected
| Fixed in– |
GitHubharfbuzzpkg:github/harfbuzzOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
HarfBuzz 8.0.0 through 14.6.0 contains an out-of-bounds write vulnerability in the experimental WebAssembly shaper because the font_glyph_to_string import has a wrong WAMR signature. Attackers can supply a crafted font whose wasm module places the output buffer near linear memory's end, writing glyph-name bytes into host memory to crash or corrupt applications.
References
- github.com/harfbuzz/harfbuzz/pull/6414 (opens in a new tab)
- github.com/harfbuzz/harfbuzz/commit/5e821de8256d01780566b5c8ab7886fae4c93da8 (opens in a new tab)
- github.com/harfbuzz/harfbuzz/blob/14.6.0/src/hb-wasm-api-list.hh (opens in a new tab)
- github.com/harfbuzz/harfbuzz/blob/14.6.0/src/hb-wasm-api-font.hh (opens in a new tab)
- vulncheck.com/advisories/harfbuzz-8.0.0-through-14.6.0-out-of-bounds-write-via-webassembly-font-glyph-to-string (opens in a new tab)