Is CVE-2026-105840 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-105840 being exploited in the wild.

How severe is CVE-2026-105840?

High severity, with a CVSS score of 7.5, published 6 October 2026.

Is there a fix for CVE-2026-105840?

Yes: fixed in 0.13.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-105840 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-105840?

Check whether you run Uwe Ohse Lrzsz 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.

CVE-2026-105840: lrzsz path traversal in lrz restricted mode

CVE-2026-105840 · Severity: high · CVSS 7.5 · Published 2026-10-06

lrzsz is a file transfer utility that implements XMODEM, YMODEM, and ZMODEM protocols. A flaw in the restricted mode of the lrz receive utility allows a malicious sender to write files to arbitrary locations on the receiving system by using absolute file paths, potentially overwriting critical files or gaining code execution.

Technologies: Uwe Ohse Lrzsz. Vendors: Uwe Ohse.

Quick answers

Is CVE-2026-105840 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-105840 being exploited in the wild.
How severe is CVE-2026-105840?: High severity, with a CVSS score of 7.5, published 6 October 2026.
Which products and versions are affected?: Uwe Ohse Lrzsz before 0.13.0.
Is there a fix for CVE-2026-105840?: Yes: fixed in 0.13.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-105840 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-105840?: Check whether you run Uwe Ohse Lrzsz 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

Fixed in: 0.13.0

Technical details

The lrz receive utility's checkpath() function in src/lrz.c only blocks relative path traversal sequences (../) unless compiled with --enable-pubdir, allowing attackers to bypass path restrictions using absolute pathnames or carefully crafted filenames. This affects systems relying on restricted mode as a security boundary, enabling remote file write and overwrite capabilities from a network-based ZMODEM sender.

Affected products

Uwe Ohse lrzsz before 0.13.0

Timeline

2026-10-06: disclosed
2026-09: patched: Version 0.13.0 released with security fixes

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.