CVE-2026-13165

Description

SzafirHost verifies the downloaded native library archive with one JarFile parser (reading the Central Directory) but extracts native libraries with JarInputStream parser (reading sequentially from local file headers). An attacker who controls the served archive can insert a malicious DLL/SO/DYLIB as a local-file-header entry between the last legitimate entry and the Central Directory, without adding it to the Central Directory. The signature verifier never sees the injected entry and accepts the archive as validly signed; the extractor reads it sequentially and writes the attacker library to the native temp directory with no hash check), while the archive-size check still passes. This can lead to remote code execution. This issue was fixed in version 1.2.2.

EPSS — Exploit Prediction

0.0042

Probability of exploitation

0.34%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-434 Unrestricted Upload

References

Other References

https://cert.pl/posts/2026/06/CVE-2026-13165 https://www.elektronicznypodpis.pl/

Frequently Asked Questions

What is CVE-2026-13165? +

SzafirHost verifies the downloaded native library archive with one JarFile parser (reading the Central Directory) but extracts native libraries with JarInputStream parser (reading sequentially from local file headers). An attacker who controls the served archive can insert a malicious DLL/SO/DYLIB as a local-file-header entry between the last legitimate entry and the Central Directory, without adding it to the Central Directory. The signature verifier never sees the injected entry and accepts the archive as validly signed; the extractor reads it sequentially and writes the attacker library to the native temp directory with no hash check), while the archive-size check still passes. This can lead to remote code execution. This issue was fixed in version 1.2.2.

How do I check if I'm vulnerable to CVE-2026-13165? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-3219

pip handles concatenated tar and ZIP files as ZIP files regardless of filename or whether a file is both a …

CVE-2024-43662

The <redacted>.exe or <redacted>.exe CGI binary can be used to upload arbitrary files to /tmp/upload/ or /tmp/ respectively as any …

CVE-2026-41517

Emlog is an open source website building system. Prior to version 2.6.11, insecure plugin upload functionality allows attackers to upload …

CVE-2026-5482

Responsive FileManager's allows an unauthenticated attacker to upload files of any type and extension without restriction using dialog.php endpoint, leading …

CVE-2026-34027

The Wertheim SafeController Software, AssemblyVersion 6.15.8328.28014, contains insufficient server-side file type validation in the /safe/contract/uploadcustomdocuments endpoint. The application validates uploaded …

CVE-2019-25714

Seeyon OA A8 contains an unauthenticated arbitrary file write vulnerability in the /seeyon/htmlofficeservlet endpoint that allows remote attackers to write …