CVE-2021-46828

In libtirpc before 1.3.3rc1, remote attackers could exhaust the file descriptors of a process that uses libtirpc because idle TCP connections are mishandled. This can, in turn, lead to an svc_run infinite loop without accepting new connections.

Published: 2022-07-20 Last update: 2025-05-05 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-46828 is rated Moderate Risk (57.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.20%). 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-2021-46828

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 2026-01-24 0.92% 1.20% +0.28%
2 2025-12-28 1.20% 0.92% -0.28%
3 2025-11-21 — 1.20% —

Full EPSS history (24 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-46828

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]
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 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-46828

OS Trackers for CVE-2021-46828

vendor priority summary link
alpine — CVE-2021-46828: 1 source package rows (libtirpc); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 7, open 0. https://security.alpinelinux.org/vuln/CVE-2021-46828
debian not yet assigned CVE-2021-46828 not yet assigned priority: Debian including 1 source packages (libtirpc), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-46828
gentoo normal CVE-2021-46828: 1 GLSA(s) (202210-33), 1 atom(s) (net-libs/libtirpc); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-46828
redhat medium — https://access.redhat.com/security/cve/CVE-2021-46828
suse high CVE-2021-46828 severity important: SUSE including 611 source package names (0.0.17-1.1:libtirpc-netconfig-1.2.6-150300.3.14.1, 0.0.17-1.1:libtirpc3-1.2.6-150300.3.14.1, …), 1482 product×package rows across 534 product lines (Container bci/bci-init, Container bci/bci-sle15-kernel-module-devel, … (534 product lines)): Fixed 1381, Known Affected 100, Known Not Affected 1. https://www.suse.com/security/cve/CVE-2021-46828/
ubuntu medium CVE-2021-46828 medium priority: Ubuntu including 2 source packages (libtirpc, ntirpc), 28 status rows across 14 suites (bionic, focal, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 19, released 4, ignored 2, DNE 1, needed 1, needs-triage 1. https://ubuntu.com/security/CVE-2021-46828

Affected software / configurations for CVE-2021-46828

Vendor Product Version Raw CPE
libtirpc_project libtirpc < 1.3.3 cpe:2.3:a:libtirpc_project:libtirpc:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2021-46828

cvelogic Threat Intelligence