How severe is CVE-2023-6681?

CVE-2023-6681 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2023-6681?

CVE-2023-6681 affects the following packages: jwcrypto (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2023-6681?

Update jwcrypto to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-6681 is resolved across your whole dependency graph.

How do I detect CVE-2023-6681 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jwcrypto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2023-6681 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2023-6681 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-6681 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-6681?

CVE-2023-6681 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 59th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2023-6681?

CVE-2023-6681 is classified as Uncontrolled Resource Consumption (CWE-400). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2023-6681 published, and has it been updated?

CVE-2023-6681 was published on February 12, 2024 and was last updated on November 5, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

MEDIUM severity

CVE-2023-6681 — jwcrypto

MEDIUMFix: latchset/jwcrypto@d2655d3

CVE-2023-6681 is a medium-severity (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in jwcrypto. A fix is available for jwcrypto — see the affected versions and patch details below.

Jwcrypto: denail of service via specifically crafted jwe

Also known asGHSA-cw2r-4p82-qv79PYSEC-2024-104

Published

Feb 12, 2024

Updated

Nov 5, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-6681.

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs59th percentile — riskier than 59% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍jwcrypto

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Denial of Service, Applications that allow the use of the PBKDF2 algorithm.

Patches

A patch is available that sets the maximum number of default rounds.

Workarounds

Applications that do not need to use PBKDF2 should simply specify the algorithms use and exclude it from the list. Applications that need to use the algorithm should upgrade to the new version that allows to set a maximum rounds number.

Acknowledgement

The issues was reported by Jingcheng Yang and Jianjun Chen from Sichuan University and Zhongguancun Lab

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`jwcrypto`	all versions	1.5.1`pip install --upgrade 'jwcrypto==1.5.1'`

Affected Products

6 products · 8 configurations

fedorafedoraproject

2 versions

3839

Application

jwcryptolatchset

< 1.5.1

range

enterprise linuxredhat

2 versions

8.09.0

enterprise linux for arm 64redhat

1 version

8.0

enterprise linux for ibm z systemsredhat

1 version

8.0

enterprise linux for power little endianredhat

1 version

8.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jwcrypto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update jwcrypto to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-6681 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

The identified vulnerability within the jwcrypto package, presents a moderate severity concern rather than a important one due to several mitigating factors. While the unbounded PBES2 Count value in PBKDF2 algorithms can potentially facilitate a Denial of Service (DoS) attack, its severity is tempered by the fact that…

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Source: Red Hat security advisory for CVE-2023-6681 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Enterprise Linux 8	`idm:client-8100020240417004735.143e9e98`	RHSA-2024:3267
Red Hat Enterprise Linux 9	`python-jwcrypto-0:1.5.6-2.el9`	RHSA-2024:9281

Frequently Asked Questions

### Impact Denial of Service, Applications that allow the use of the PBKDF2 algorithm. ### Patches A [patch](https://github.com/latchset/jwcrypto/commit/d2655d370586cb830e49acfb450f87598da60be8) is available that sets the maximum number of default rounds. ### Workarounds Applications that do not need to use PBKDF2 should simply specify the algorithms use and exclude it from the list. Applications that need to use the algorithm should upgrade to the new version that allows to set a maximum rounds number. ### Acknowledgement The issues was reported by Jingcheng Yang and Jianjun Chen from Sich