CVE-2019-11922

A race condition in the one-pass compression functions of Zstandard prior to version 1.3.8 could allow an attacker to write bytes out of bounds if an output buffer smaller than the recommended size was used.

Published: 2019-07-25 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-11922 is rated Moderate Risk (56.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.63%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-11922

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 1.00% 0.63% -0.37%
2 2025-11-18 0.63% 1.00% +0.37%
3 2025-09-26 — 0.63% —

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-11922

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.0 HIGH
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2019-11922

OS Trackers for CVE-2019-11922

vendor priority summary link
alpine high CVE-2019-11922: 1 source package rows (zstd); 9 state rows across 9 repos (3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 9, open 0. https://security.alpinelinux.org/vuln/CVE-2019-11922
debian not yet assigned CVE-2019-11922 not yet assigned priority: Debian including 1 source packages (libzstd), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-11922
redhat medium — https://access.redhat.com/security/cve/CVE-2019-11922
suse — — https://www.suse.com/security/cve/CVE-2019-11922/
ubuntu medium CVE-2019-11922 medium priority: Ubuntu including 1 source packages (libzstd), 12 status rows across 12 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, trusty, upstream, xenial): not-affected 8, released 3, DNE 1. https://ubuntu.com/security/CVE-2019-11922

Affected software / configurations for CVE-2019-11922

Vendor Product Version Raw CPE
facebook zstandard < 1.3.8 cpe:2.3:a:facebook:zstandard:*:*:*:*:*:*:*:*

References for CVE-2019-11922

cvelogic Threat Intelligence