CVE-2021-46828: In libtirpc before 1.3.3rc1, remote attackers could exhaust the file descriptors of a process that uses libtir

Q: How do I fix CVE-2021-46828?

libtirpc: upgrade to 1.3.3; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2021-46828 being exploited?

CVE-2021-46828 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-46828 affect?

CVE-2021-46828 affects libtirpc, debian linux. Severity is high (CVSS 7.5). 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 connecti

Q: How urgent is CVE-2021-46828?

Priority 58/100. High severity; Remotely exploitable, no login, no user action; On your watchlist

This month

HIGH 7.5REMOTEWATCHLISTUPGRADEMITIGATE

CVE-2021-46828 is a high-severity flaw (CVSS 7.5) affecting libtirpc, debian linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	3.2% (top 12%)
CISA exploited list	No
Weakness	CWE-755, CWE-835
Published	2022-07-20
Last modified	2026-10-14

Publisher (CNA): MITRE · Vendor: debian · libtirpc project

Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-07-20 06:15 UTCPublished CVE record published
2026-10-14 13:17 UTCUpdated Record last modified

libtirpc project libtirpc UPGRADE

Affected: < 1.3.3

Fixed in: 1.3.3

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy libtirpc || rpm -q libtirpc || libtirpc --version

2. UPGRADE to 1.3.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade libtirpc

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade libtirpc

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

debian debian linux MITIGATE

Affected: 10.0 · 11.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-46828?

libtirpc: upgrade to 1.3.3; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-46828 being exploited?

CVE-2021-46828 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-46828 affect?

CVE-2021-46828 affects libtirpc, debian linux. Severity is high (CVSS 7.5). 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 connecti

How urgent is CVE-2021-46828?

Priority 58/100. High severity; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Debian vulnerabilities

Related CVEs

CVE-2018-14622 HIGH 7.5 UPGRADE MITIGATE A null-pointer dereference vulnerability was found in libtirpc before version 0.3.3-rc3
CVE-2018-14621 MEDIUM 5.3 UPGRADE An infinite loop vulnerability was found in libtirpc before version 1.0.2-rc2
CVE-2017-8779 HIGH 7.5 UPGRADE UPGRADE rpcbind through 0.2.4, LIBTIRPC through 1.0.1 and 1.0.2-rc through 1.0.2-rc3, and NTIRPC through 1.4.3 do not
CVE-2013-1950 MEDIUM 4.3 UPGRADE The svc_dg_getargs function in libtirpc 0.2.3 and earlier allows remote attackers to cause a denial of service

References

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