Is there a public exploit for CVE-2026-63499?

No public exploit for CVE-2026-63499 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-63499?

CVE-2026-63499 scores CVSS 6.9 (v4.0), rated medium.

What does CVE-2026-63499 affect?

CVE-2026-63499 affects zeroturnaround zt-zip.

6.9 Medium

zt-zip is a Java library that provides convenience methods for ZIP archive manipulation.

CVE-2026-63499

zt-zip is a Java library that provides convenience methods for ZIP archive manipulation. Prior to 1.18.1, ZipUtil.unpack(...) can apply stored ZIP-entry permissions to the extraction output directory when an entry name such as / or ./ resolves to that directory itself. Because the path traversal checks permit self-referencing entries that do not escape the destination, the unpacker's permission-handling path can replace restrictive output-directory permissions with attacker-supplied permissions. This affects applications that unpack untrusted ZIP files, and POSIX systems demonstrate the issue directly, while ZTFilePermissionsUtil.fetchDefaultStrategy provides fallback permission handling on other supported systems. This issue is fixed in version 1.18.1.

Assessment

CVSS: 6.9 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 3 November 2026
Affected: zeroturnaround · zt-zip
Assigner: GitHub_M

CVSS vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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