CVE-2021-38202

fs/nfsd/trace.h in the Linux kernel before 5.13.4 might allow remote attackers to cause a denial of service (out-of-bounds read in strlen) by sending NFS traffic when the trace event framework is being used for nfsd.

Published: 2021-08-08 Last update: 2026-05-12 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-38202 is rated Moderate Risk (58.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.45%). 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-2021-38202

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 2026-05-12 1.06% 1.45% +0.40%
2 2026-03-25 1.45% 1.06% -0.40%
3 2025-11-21 — 1.45% —

Full EPSS history (19 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-38202

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2021-38202

GitHub Security Advisory for CVE-2021-38202

GHSA-j8f3-cxf7-rj22 · Severity: high — fs/nfsd/trace.h in the Linux kernel before 5.13.4 might allow remote attackers to cause a denial...

OS Trackers for CVE-2021-38202

vendor priority summary link
debian unimportant CVE-2021-38202 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-38202
redhat high — https://access.redhat.com/security/cve/CVE-2021-38202
ubuntu medium CVE-2021-38202 medium priority: Ubuntu including 123 source packages (linux, linux-allwinner, …), 1326 status rows across 12 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): DNE 977, not-affected 195, released 103, ignored 51. https://ubuntu.com/security/CVE-2021-38202

Affected software / configurations for CVE-2021-38202

Vendor Product Version Raw CPE
linux linux_kernel < 5.13.4 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
netapp hci_bootstrap_os — cpe:2.3:o:netapp:hci_bootstrap_os:-:*:*:*:*:*:*:*
netapp hci_management_node — cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
netapp solidfire — cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
netapp element_software — cpe:2.3:a:netapp:element_software:-:*:*:*:*:*:*:*

References for CVE-2021-38202

cvelogic Threat Intelligence