Vulnerability record · CVE-2026-4851 · published 29 March 2026
CVE-2026-4851: Casiano grid\ deserialization of untrusted data vulnerability
Casiano · Grid\
GRID::Machine versions through 0.127 for Perl allows arbitrary code execution via unsafe deserialization. GRID::Machine provides Remote Procedure Calls (RPC) over SSH for Perl. The client connects to remote hosts to execute code on them. A compromised or malicious remote host can execute arbitrary code back on the client through unsafe deserialization in the RPC protocol. read_operation() in lib/GRID/Machine/Message.pm deserialises values from the remote side using eval() $arg .= '$VAR1'; my $val = eval "no strict; $arg"; # line 40-41 $arg is raw bytes from the protocol pipe. A compromised remote host can embed arbitrary perl in the Dumper-formatted response: $VAR1 = do { system("..."); }; This executes on the client silently on every RPC call, as the return values remain correct. This functionality is by design but the trust requirement for the remote host is not documented in the distribution.
Description
GRID::Machine versions through 0.127 for Perl allows arbitrary code execution via unsafe deserialization. GRID::Machine provides Remote Procedure Calls (RPC) over SSH for Perl. The client connects to remote hosts to execute code on them. A compromised or malicious remote host can execute arbitrary code back on the client through unsafe deserialization in the RPC protocol. read_operation() in lib/GRID/Machine/Message.pm deserialises values from the remote side using eval() $arg .= '$VAR1'; my $val = eval "no strict; $arg"; # line 40-41 $arg is raw bytes from the protocol pipe. A compromised remote host can embed arbitrary perl in the Dumper-formatted response: $VAR1 = do { system("..."); }; This executes on the client silently on every RPC call, as the return values remain correct. This functionality is by design but the trust requirement for the remote host is not documented in the distribution.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://www.openwall.com/lists/oss-security/2026/03/26/6 | Mailing List |
| http://www.openwall.com/lists/oss-security/2026/03/26/6 | Mailing List |
Track CVE-2026-4851 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-4851), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
