CVE-2026-105841
lrzsz before 0.13.0 OS Command Injection via lrz Pipe Mode
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.7
lrzsz before 0.13.0 OS Command Injection via lrz Pipe Mode
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
CVE-2026-105841- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
EUVDEUVD-2026-93393
7.7
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
EUVD-2026-93393- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-w9c3-4vq7-c452
7.7
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's...
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
GHSA-w9c3-4vq7-c452- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
NVD
7.7
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
CVE-2026-105841- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-105841
7.5
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
DEBIAN-CVE-2026-105841- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVRHSA-2026:83525
7.5
Red Hat Security Advisory: lrzsz security, bug fix, and enhancement update
- Record
RHSA-2026:83525- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Show 11 moreShow less
OSVRLSA-2026:83525
7.5
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
-
lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
-
lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [rhel-8.10.z] (JIRA:Rocky Linux-282148)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
RLSA-2026:83525- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVRLSA-2026:86056
7.5
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
-
lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
-
lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [rhel-10.2.z] (JIRA:Rocky Linux-282106)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
RLSA-2026:86056- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVRLSA-2026:89755
7.5
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
-
lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
-
lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [rhel-9.8.z] (JIRA:Rocky Linux-282108)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
RLSA-2026:89755- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-105841
7.7
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
UBUNTU-CVE-2026-105841- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVALSA-2026:83525 No score
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
- lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
- lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [almalinux-8.10.z] (JIRA:AlmaLinux-282148)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
ALSA-2026:83525- Updated
- 2026-11-02
OSVALSA-2026:86056 No score
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
- lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
- lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [almalinux-10.2.z] (JIRA:AlmaLinux-282106)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
ALSA-2026:86056- Updated
- 2026-11-02
OSVALSA-2026:89755 No score
Important: lrzsz security, bug fix, and enhancement update
Lrzsz (consisting of lrz and lsz) is a cosmetically modified zmodem/ymodem/xmodem package built from the public-domain version of the rzsz package. Lrzsz was created to provide a working GNU copylefted Zmodem solution for Linux systems.
Security Fix(es):
- lrzsz: lrzsz: Arbitrary file overwrite via absolute path traversal in restricted mode (CVE-2026-105840)
- lrzsz: lrzsz: Arbitrary command execution via crafted file names in pipe mode (CVE-2026-105841)
Bug Fix(es) and Enhancement(s):
- lrzsz: segfault with -s [almalinux-9.8.z] (JIRA:AlmaLinux-282108)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
- Record
ALSA-2026:89755- Updated
- 2026-11-02
OSVAZL-106673 No score
CVE-2026-105841 affecting package lrzsz 0.12.20-50
lrzsz before 0.13.0 contains an OS command injection vulnerability in the lrz receive utility's pipe mode that allows remote senders to execute commands by supplying crafted filenames. When lrz runs under a suffixed name such as lrztar, procheader() in src/lrz.c passes the unescaped ZMODEM/YMODEM filename to popen(), so shell metacharacters execute as the receiving user.
- Record
AZL-106673- Updated
- 2026-11-05
OSVCLSA-2026-1792053113 No score
lrzsz: Fix of 3 CVEs
- CVE-2026-105840: lrz: reject absolute and escaping paths in restricted mode
- CVE-2026-105841: lrz: remove piping received files to a shell command
- CVE-2026-105842: lrz: terminate received data and bound file name length
- Record
CLSA-2026-1792053113- Updated
- 2026-11-02
OSVCLSA-2026-1792422501 No score
Fix CVE(s): CVE-2026-105840, CVE-2026-105841, CVE-2026-105842
- SECURITY UPDATE: absolute path names accepted in restricted mode
- debian/patches/CVE-2026-105840.patch: reject absolute path names in restricted mode in checkpath() in src/lrz.c and wcs() in src/lsz.c, not only in PUBDIR builds
- CVE-2026-105840
- SECURITY UPDATE: command injection via the pipe mode
- debian/patches/CVE-2026-105841.patch: remove the pipe mode that ran received files through a shell command when lrz was invoked as rzCOMMAND, in src/lrz.c
- CVE-2026-105841
- SECURITY UPDATE: heap buffer overflow via a long file name
- debian/patches/CVE-2026-105842.patch: allocate the received path name with strdup() instead of a fixed PATH_MAX*2 buffer, and NUL-terminate the ZFILE subpacket, in src/lrz.c
- CVE-2026-105842
- Record
CLSA-2026-1792422501- Updated
- 2026-11-02
OSVCLSA-2026-1792503867 No score
lrzsz: Fix of 3 CVEs
- CVE-2026-105840: reject absolute path names in restricted mode in lrz (received files) and lsz (sent files), not only in PUBDIR builds
- CVE-2026-105841: remove the pipe mode that ran received files through a shell command when lrz was invoked as rzCOMMAND
- CVE-2026-105842: allocate the received path name with strdup() instead of a fixed PATH_MAX*2 buffer, and NUL-terminate the ZFILE subpacket
- Record
CLSA-2026-1792503867- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
lrzszAlmaLinux:8 From an advisory covering 2 CVEs |
before 0.12.20-46.el8_10 | 0.12.20-46.el8_10 |
lrzszAlmaLinux:10 From an advisory covering 2 CVEs |
before 0.12.20-69.el10_2 | 0.12.20-69.el10_2 |
lrzszAlmaLinux:9 From an advisory covering 2 CVEs |
before 0.12.20-58.el9_8 | 0.12.20-58.el9_8 |
lrzszAzure Linux:3 |
through 0.12.20-50 | None known |
lrzszTuxCare:AlmaLinux:9.2 From an advisory covering 3 CVEs |
before 0.12.20-55.el9.tuxcare.els1 | 0.12.20-55.el9.tuxcare.els1 |
lrzszTuxCare:Ubuntu:18.04 From an advisory covering 3 CVEs |
before 0.12.21-10~build0.18.04.1+tuxcare.els1 | 0.12.21-10~build0.18.04.1+tuxcare.els1 |
lrzszTuxCare:AlmaLinux:9.6 From an advisory covering 3 CVEs |
before 0.12.20-55.el9_6.tuxcare.els1 | 0.12.20-55.el9_6.tuxcare.els1 |
lrzszDebian:12 |
All versions, plus listed versions 0.12.21-100.12.21-110.12.21rc-0.10.12.21rc-0.20.12.21rc-0.3 Show 6 moreShow less0.12.21rc-10.12.21rc-20.12.21rc-30.12.21rc-40.12.21rc-50.13.1-1 |
None known |
lrzszDebian:13 |
All versions, plus listed versions 0.12.21rc-0.20.12.21rc-0.30.12.21rc-10.12.21rc-20.12.21rc-30.12.21rc-40.12.21rc-50.13.1-1 |
None known |
lrzszDebian:14 |
before 0.13.1-1, plus listed versions 0.12.21rc-0.20.12.21rc-0.30.12.21rc-10.12.21rc-20.12.21rc-30.12.21rc-40.12.21rc-5 |
0.13.1-1 |
Show 14 moreShow less
| Package | Affected | Fixed |
|---|---|---|
lrzszRed Hat:enterprise_linux:8::baseos From an advisory covering 2 CVEs |
before 0:0.12.20-46.el8_10 | 0:0.12.20-46.el8_10 |
lrzsz-debuginfoRed Hat:enterprise_linux:8::baseos From an advisory covering 2 CVEs |
before 0:0.12.20-46.el8_10 | 0:0.12.20-46.el8_10 |
lrzsz-debugsourceRed Hat:enterprise_linux:8::baseos From an advisory covering 2 CVEs |
before 0:0.12.20-46.el8_10 | 0:0.12.20-46.el8_10 |
lrzszRocky Linux:8 From an advisory covering 2 CVEs |
before 0:0.12.20-46.el8_10 | 0:0.12.20-46.el8_10 |
lrzszRocky Linux:10 From an advisory covering 2 CVEs |
before 0:0.12.20-69.el10_2 | 0:0.12.20-69.el10_2 |
lrzszRocky Linux:9 From an advisory covering 2 CVEs |
before 0:0.12.20-58.el9_8 | 0:0.12.20-58.el9_8 |
lrzszUbuntu:14.04:LTS |
All versions, plus listed versions 0.12.21-50.12.21-70.12.21-10~build0.14.04.1 |
None known |
lrzszUbuntu:16.04:LTS |
All versions, plus listed versions 0.12.21-80.12.21-10~build0.16.04.1 |
None known |
lrzszUbuntu:18.04:LTS |
All versions, plus listed versions 0.12.21-80.12.21-8build10.12.21-10~build0.18.04.1 |
None known |
lrzszUbuntu:20.04:LTS |
All versions, plus listed versions 0.12.21-10 |
None known |
lrzszUbuntu:22.04:LTS |
All versions, plus listed versions 0.12.21-10 |
None known |
lrzszUbuntu:24.04:LTS |
All versions, plus listed versions 0.12.21-100.12.21-110.12.21-11build1 |
None known |
lrzszUbuntu:26.10 |
All versions, plus listed versions 0.12.21rc-0.30.12.21rc-10.12.21rc-20.12.21rc-4 |
None known |
lrzszUbuntu:26.04:LTS |
All versions, plus listed versions 0.12.21rc-0.20.12.21rc-0.3 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| facts | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-105841 is a high vulnerability (CVSS 7.7) in Microsoft Lrzsz, published October 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.94%, the 61st percentile. Fixed in lrzsz 0.13.1-1.
References
ohse.de/uwe/software/lrzsz/NEWS-0.13.0.html
ohse.de/uwe/software/lrzsz.html
vulncheck.com/advisories/lrzsz-before-0.13.0-os-command-injection-via-lrz-pipe-mode
nvd.nist.gov/vuln/detail/CVE-2026-105841
github.com/advisories/GHSA-w9c3-4vq7-c452
access.redhat.com/errata/RHSA-2026:83525
Show 26 moreShow less
access.redhat.com/security/cve/CVE-2026-105840
access.redhat.com/security/cve/CVE-2026-105841
bugzilla.redhat.com/2546590
bugzilla.redhat.com/2546595
errata.almalinux.org/8/ALSA-2026-83525.html
access.redhat.com/errata/RHSA-2026:86056
errata.almalinux.org/10/ALSA-2026-86056.html
access.redhat.com/errata/RHSA-2026:89755
errata.almalinux.org/9/ALSA-2026-89755.html
errata.tuxcare.com/els_os/almalinux9.2esu/CLSA-2026-1792053113.html
nvd.nist.gov/vuln/detail/CVE-2026-105840
nvd.nist.gov/vuln/detail/CVE-2026-105842
errata.tuxcare.com/els_os/ubuntu18.04els/CLSA-2026-1792422501.html
errata.tuxcare.com/els_os/tuxcare9.6esu/CLSA-2026-1792503867.html
security-tracker.debian.org/tracker/CVE-2026-105841
access.redhat.com/security/updates/classification
bugzilla.redhat.com/show_bug.cgi?id=2546590
bugzilla.redhat.com/show_bug.cgi?id=2546595
security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_83525.json
cve.org/CVERecord?id=CVE-2026-105840
vulncheck.com/advisories/lrzsz-before-0.13.0-path-traversal-via-lrz-restricted-mode-checkpath
cve.org/CVERecord?id=CVE-2026-105841
errata.rockylinux.org/RLSA-2026:83525
errata.rockylinux.org/RLSA-2026:86056
errata.rockylinux.org/RLSA-2026:89755
ubuntu.com/security/CVE-2026-105841