CVE-2026-63436: zeroturnaround zt-zip · Path Traversal
Affects zeroturnaround zt-zipSource CVE Database V5
Not known to be exploited · CVSS 6.1 Medium : upgrade to 1.18.0 when convenient.
Data as of 3 Nov 2026, 18:28 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 6.1 |
|---|
- Patch
- Available – fixed in 1.18.0
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:LExploitation evidence
Disclosed: evidence found.
CVE published 3 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 3 Nov 2026.
What to do
Upgrade zt-zip and com.zeroturnaround/zt-zip to 1.18.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| zeroturnaroundzt-zip | Affected
| Fixed in
|
Mavencom.zeroturnaround/zt-zippkg:maven/com.zeroturnaround/zt-zipOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to zt-zip version 1.18.0 or later, where the vulnerability is fixed by adding destination-boundary validation. Applications extracting untrusted archives should avoid using the vulnerable API and instead use ZipUtil.unpack(...) which already performs the necessary validation.
Description
A path traversal vulnerability (CWE-22) exists in zeroturnaround zt-zip versions prior to 1.18.0. The Zips.get(zip).unpack().destination(outputDir).process() API constructs output file paths directly from ZIP entry names without validating that files remain within the intended output directory. This allows crafted ZIP entries with parent-directory traversal sequences to write files outside the designated output directory. The issue is fixed in version 1.18.0.
References
- github.com/zeroturnaround/zt-zip/security/advisories/GHSA-52c6-99qm-3hqr (opens in a new tab)
- github.com/zeroturnaround/zt-zip/pull/180 (opens in a new tab)
- github.com/zeroturnaround/zt-zip/commit/59a76ad576b0fcd50ea018e3608afb946c1492fd (opens in a new tab)
- github.com/zeroturnaround/zt-zip/releases/tag/v1.18.0 (opens in a new tab)