Is CVE-2026-105842 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-105842 being exploited in the wild.

How severe is CVE-2026-105842?

Medium severity, with a CVSS score of 6.4, published 6 October 2026.

Is there a fix for CVE-2026-105842?

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

How is CVE-2026-105842 attacked?

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

Am I affected by CVE-2026-105842?

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-2026-105842: lrzsz heap buffer overflow in procheader

CVE-2026-105842 · Severity: medium · CVSS 6.4 · Published 2026-10-06

lrzsz is a Unix utility for transferring files using XMODEM, YMODEM, and ZMODEM protocols. A heap buffer overflow in the lrz receive utility can be triggered when a malicious sender supplies overlong filenames during ZMODEM file transfers, allowing an attacker to crash the program or potentially execute arbitrary code.

Technologies: Uwe Ohse Lrzsz. Vendors: Uwe Ohse.

Quick answers

Is CVE-2026-105842 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-105842 being exploited in the wild.
How severe is CVE-2026-105842?: Medium severity, with a CVSS score of 6.4, published 6 October 2026.
Which products and versions are affected?: Uwe Ohse Lrzsz before 0.13.0.
Is there a fix for CVE-2026-105842?: Yes: fixed in lrzsz 0.13.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-105842 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-105842?: 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: lrzsz 0.13.0

Technical details

The procheader() function in lrz copies sender-supplied filenames into a fixed-size Pathname buffer without proper length validation, allowing filenames up to 8192 bytes to overflow the heap via sprintf() in pipe mode or strcpy(). The vulnerability requires a ZMODEM file transfer initiated by a malicious sender and can result in heap memory corruption, denial of service, or potential code execution.

Affected products

Uwe Ohse lrzsz before 0.13.0

Timeline

2026-10-06: disclosed
2026-09: patched: version 0.13.0 released

References

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