CVE-2026-4851

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-03-29. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 9.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
9.8
EG Score
9.8(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
—
EPSS %ILE
—
KEV
Not listed

Published

March 29, 2026

Last Modified

June 17, 2026

Advisory Details (2)

Auto-updated Jul 27, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

oss-security - CVE-2026-4851: remote-to-local code execution in GRID::Machine

http://www.openwall.com/lists/oss-security/2026/03/26/6
generic🟡 PoC Available

oss-security - CVE-2026-4851: remote-to-local code execution in GRID::Machine

https://www.openwall.com/lists/oss-security/2026/03/26/6

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 2× in last 7d / 2× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-27 14:19 UTCEG score recompute
  2. 2026-07-27 14:18 UTCGHSA enrichment

Related CVEs(same CWE)

Frequently asked(4)

What is CVE-2026-4851?
CVE-2026-4851 is a critical vulnerability published on March 29, 2026. 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…
When was CVE-2026-4851 disclosed?
CVE-2026-4851 was first published in the National Vulnerability Database on March 29, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-4851?
CVE-2026-4851 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-4851?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-4851, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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