CVE-2024-25190: l8w8jwt 2.2.1 uses memcmp (which is not constant time) to verify authentication, which makes it easier to bypa

This week

CRITICAL 9.8REMOTEDOWNGRADE

CVE-2024-25190 is a critical-severity flaw (CVSS 9.8) affecting l8w8jwt. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

l8w8jwt 2.2.1 uses memcmp (which is not constant time) to verify authentication, which makes it easier to bypass authentication via a timing side channel.

Why this priority

Critical severity
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	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.9% (top 40%)
CISA exploited list	No
Weakness	CWE-203
Published	2024-02-08
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: glitchedpolygons

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

Am I affected?

Timeline

2024-02-08 17:15 UTCPublished CVE record published
2026-06-17 07:15 UTCUpdated Record last modified

glitchedpolygons l8w8jwt DOWNGRADE

Affected: 2.2.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.2.1

1. Check installed version

apt-cache policy l8w8jwt || rpm -q l8w8jwt || l8w8jwt --version

2. No fixed release: DOWNGRADE to a release before 2.2.1 (Debian / Ubuntu)

apt-cache madison l8w8jwt sudo apt install l8w8jwt=<VERSION_BEFORE_2.2.1> sudo apt-mark hold l8w8jwt

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

dnf --showduplicates list l8w8jwt sudo dnf downgrade l8w8jwt-<VERSION_BEFORE_2.2.1> sudo dnf versionlock add l8w8jwt

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-2024-25190?

l8w8jwt: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2024-25190 being exploited?

CVE-2024-25190 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-2024-25190 affect?

CVE-2024-25190 affects l8w8jwt. Severity is critical (CVSS 9.8). l8w8jwt 2.2.1 uses memcmp (which is not constant time) to verify authentication, which makes it easier to bypass authentication via a timing side channel.

How urgent is CVE-2024-25190?

Priority 59/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

References

← Back to latest CVEs