CVE-2022-4899 Overview
CVE-2022-4899 is a buffer overrun vulnerability in Facebook Zstandard (zstd) version 1.4.10. The flaw allows an attacker to trigger a buffer overrun by supplying an empty string as an argument to the zstd command line tool. The issue is classified under CWE-400 (Uncontrolled Resource Consumption) and primarily impacts availability of systems using the affected version. Successful exploitation can cause the zstd process to crash, resulting in denial of service. The vulnerability was published to the National Vulnerability Database (NVD) on March 31, 2023.
Critical Impact
An attacker can trigger a buffer overrun in the zstd command line tool by passing an empty string argument, causing process termination and impacting service availability.
Affected Products
- Facebook Zstandard version 1.4.10
- Downstream Fedora packages bundling vulnerable zstd builds
- NetApp products incorporating the affected zstd library (see NetApp advisory)
Discovery Timeline
- 2023-03-31 - CVE-2022-4899 published to NVD
- 2025-02-18 - Last updated in NVD database
Technical Details for CVE-2022-4899
Vulnerability Analysis
The vulnerability resides in the zstd command line utility shipped with Zstandard 1.4.10. When the binary receives an empty string as a command line argument, internal argument parsing logic fails to validate the input length before performing buffer operations. This results in a buffer overrun condition tracked under [CWE-400]. The flaw is reachable through the network attack vector when zstd is invoked by automated pipelines, web services, or backup systems that pass user-controlled input directly to the CLI. While the issue does not expose memory contents or allow code execution, it terminates the process and prevents legitimate compression and decompression operations. Refer to the GitHub Issue Discussion for upstream technical context.
Root Cause
The root cause is improper input validation in the zstd CLI argument handling path. The utility processes empty string inputs without first checking length boundaries, causing a downstream buffer operation to read or write past intended limits. The condition is reproducible by invoking zstd "" against the vulnerable version.
Attack Vector
Exploitation requires the attacker to influence the arguments passed to the zstd command line tool. In environments where zstd is wrapped by network-facing services, scripts, or file-processing pipelines that forward untrusted input, an attacker can supply an empty string to trigger the overrun. The result is a crash of the zstd process and a denial of service for the calling workflow.
No verified proof-of-concept code is published for this CVE. See the GitHub Issue Discussion and the NetApp Security Advisory for additional technical references.
Detection Methods for CVE-2022-4899
Indicators of Compromise
- Unexpected crashes or abnormal terminations of the zstd process on hosts running version 1.4.10.
- Repeated invocations of zstd with empty string arguments in shell history, audit logs, or pipeline logs.
- Failed compression or decompression jobs in backup, logging, or data transfer workflows that depend on zstd.
Detection Strategies
- Inventory all systems and container images to identify deployments of zstd 1.4.10 using package managers or software composition analysis tools.
- Review process execution telemetry for zstd invocations with suspicious or empty argument values.
- Correlate application error logs with zstd crashes to identify exploitation attempts against service availability.
Monitoring Recommendations
- Enable process auditing on Linux hosts to capture zstd command lines and exit codes.
- Alert on non-zero exit statuses from zstd in production pipelines and backup jobs.
- Track package versions of zstd across the fleet and flag any host still running the vulnerable 1.4.10 release.
How to Mitigate CVE-2022-4899
Immediate Actions Required
- Identify all instances of zstd 1.4.10 across servers, workstations, and container images.
- Upgrade zstd to a patched version provided by the upstream project or your distribution vendor.
- Apply distribution-specific updates such as those documented in the Fedora package announcements.
- Validate that any application invoking the zstd CLI sanitizes arguments and rejects empty inputs.
Patch Information
Facebook addressed the issue in releases following 1.4.10. Apply vendor updates referenced in the Fedora Package Announcement and the NetApp Security Advisory. Refer to the GitHub Issue Discussion for the upstream fix discussion.
Workarounds
- Restrict invocation of the zstd CLI to trusted users and validated input sources.
- Wrap zstd calls in scripts that reject empty string arguments before execution.
- Prefer library-based integrations using libzstd rather than shelling out to the CLI where feasible.
- Isolate workloads that process untrusted input through zstd using container sandboxing or resource limits.
# Configuration example: validate argument before invoking zstd
INPUT_FILE="$1"
if [ -z "$INPUT_FILE" ]; then
echo "Error: empty argument rejected" >&2
exit 1
fi
zstd "$INPUT_FILE"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
