Quick answers
- Is CVE-2026-63499 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-63499 being exploited in the wild.
- How severe is CVE-2026-63499?
- Medium severity, with a CVSS score of 4, published 3 November 2026.
- Which products and versions are affected?
- org.zeroturnaround:zt-zip (Maven) <= 1.18.0, ECOSYSTEM:introduced=0,fixed=1.18.1; ZeroTurnaround Zt-Zip prior to 1.18.1.
- Is there a fix for CVE-2026-63499?
- Yes. org.zeroturnaround:zt-zip (Maven): upgrade to 1.18.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-63499 attacked?
- It is attacked over the network or with local access, in a software library.
- Am I affected by CVE-2026-63499?
- Check whether you run org.zeroturnaround:zt-zip (Maven) or ZeroTurnaround Zt-Zip at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- org.zeroturnaround:zt-zip (Maven): upgrade to 1.18.1 or later
# set org.zeroturnaround:zt-zip to 1.18.1 in your pom.xml or build.gradle
Technical details
ZipUtil.unpack() applies stored file permissions from ZIP entries to extracted files, but failed to exclude self-referencing entries (e.g., named "/" or "./") that resolve to the output directory itself. The traversal guard permitted these entries because they do not escape the destination, but the permission handler could then replace the directory's own restrictive permissions with attacker-supplied ones. The fix adds a check to skip permission application when the entry destination is the output directory itself, rather than a file or subdirectory within it.
Affected products
- ZeroTurnaround zt-zip prior to 1.18.1
Identifiers
- CVE-2026-63499
- GHSA-v2g6-7r9j-v6px
Timeline
- 2026-11-03: disclosed
- 2026-07-01: patched