CVE-2024-11738: A flaw was found in Rustls 0.23.13 and related APIs

This week

MEDIUM 5.3REMOTEDOWNGRADE

CVE-2024-11738 is a medium-severity flaw (CVSS 5.3) affecting rustls. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A flaw was found in Rustls 0.23.13 and related APIs. This vulnerability allows denial of service (panic) via a fragmented TLS ClientHello message.

Why this priority

Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.7% (top 46%)
CISA exploited list	No
Weakness	CWE-248
Published	2024-12-06
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: rustls project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2024-12-06 15:15 UTCPublished CVE record published
2026-06-17 06:58 UTCUpdated Record last modified

rustls project rustls DOWNGRADE

Affected: 0.23.13

Fixed in: no fixed release known

Safe to downgrade to: a release before 0.23.13

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 0.23.13 (Debian / Ubuntu)

apt-cache madison rustls sudo apt install rustls=<VERSION_BEFORE_0.23.13> sudo apt-mark hold rustls

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list rustls sudo dnf downgrade rustls-<VERSION_BEFORE_0.23.13> sudo dnf versionlock add rustls

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

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-2024-11738?

rustls: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2024-11738 being exploited?

CVE-2024-11738 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-2024-11738 affect?

CVE-2024-11738 affects rustls. Severity is medium (CVSS 5.3). A flaw was found in Rustls 0.23.13 and related APIs. This vulnerability allows denial of service (panic) via a fragmented TLS ClientHello message.

How urgent is CVE-2024-11738?

Priority 42/100. Public exploit reference; Remotely exploitable, no login, no user action

References

← Back to latest CVEs