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Public proof of conceptFix available

CVE-2024-3651

A public proof of concept exists; no exploitation attested.

  • Published2024-07-07
  • Fixed in3.7
  • WeaknessCWE-1333

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability was identified in the kjd/idna library, specifically within the `idna.encode()` function, affecting version 3.6. The issue arises from the function's handling of crafted input strings, which can lead to quadratic complexity and consequently, a denial of service condition. This vulnerability is triggered by a crafted input that causes the `idna.encode()` function to process the input with considerable computational load, significantly increasing the processing time in a quadratic manner relative to the input size.

Timeline

dates in UTC
  1. 2024-07-0718:15CVE publishedNVD

Versions per branch

NVD · OSV
Kjd internationalized domain names in applications
BranchAffectedFixed in
3.7≥ 0.2, < 3.73.7
3.7≥ 0.1, < 3.73.7
3.7< 3.73.7

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As @huntr_ai, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • kjd/idna
    Affected
    • < 3.7fixed in 3.7custom

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2025-10-15

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • automation-controller-venv-towerRed Hat:ansible_automation_platform:2.4::el9all versions · fixed in 0:4.5.7-1.el9ap
  • automation-controller-venv-towerRed Hat:ansible_automation_platform:2.4::el8all versions · fixed in 0:4.5.7-1.el8ap
  • automation-hubRed Hat:ansible_automation_platform:2.4::el9all versions · fixed in 0:4.9.2-1.el9apand 2 other packages
  • automation-hubRed Hat:ansible_automation_platform:2.4::el8all versions · fixed in 0:4.9.2-1.el8apand 2 other packages
  • azWolfiall versions · fixed in 2.60.0-r0and 1 other package
  • azChainguardall versions · fixed in 2.60.0-r0and 1 other package
  • checkovWolfiall versions · fixed in 3.0.34-r1
  • checkovChainguardall versions · fixed in 3.0.34-r1

331 more package ranges on OSV.dev

Vendor advisories

  • CVE-2024-3651 Red Hat Product Security247 products fixed · 11 known affected

    python-idna: potential DoS via resource consumption via specially crafted inputs to idna.encode()

    python-idna.src (python27:2.7) as a component of Red Hat Enterprise Linux 8 · python3-idna (python27:2.7) as a component of Red Hat Enterprise Linux 8 · python2-idna as a component of Red Hat OpenShift Container Platform 3.11 · +8 more

  • RHSA-2024:8365 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: python-idna security update

  • RHSA-2024:4260 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: python-idna security update

  • RHSA-2024:3846 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: python-idna security update

  • RHSA-2024:3781 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: Red Hat Ansible Automation Platform 2.4 Product Security and Bug Fix Update

  • RHSA-2024:3543 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: python-idna security and bug fix update

2 more advisories

Full record on NVD

Fix

  1. Update Kjd internationalized domain names in applications to 3.7
  2. Vendor fix Red Hat Product Security RHSA-2024:8365 · 2 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  3. Vendor fix Red Hat Product Security RHSA-2024:3781 · 8 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 For the update to take effect, all applications using Jinja2 must be restarted.
  4. Vendor fix Red Hat Product Security RHSA-2024:3543 · 2 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
  5. Vendor fix Red Hat Product Security RHSA-2024:3466 · 229 productsFor details on how to apply this update, refer to: https://access.redhat.com/articles/11258
  6. Workaround from the vendor Red Hat Product Security RHSA-2024:8365 · 2 productsMitigation 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.
  7. No fix planned, says the vendor Red Hat Product Security CVE-2024-3651 · 1 productOut of support scope

Advisories and patches

Detection

read 2026-11-01 01:02 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

  • CISA-ADPSSVC decisionnone2024-07-07
  • NVDCVSS 3.17.5read 2026-10-23
  • CNACVSS 3.06.2known since 2026-10-23
  • CNAweakness (CWE)CWE-1333known since 2026-10-23
  • FIRST EPSSEPSS score1.4 %2026-11-08
  • PoC-in-GitHubproof of concept1known since 2026-11-01
  • OSVaffected packages—
  • GitHub AdvisoriesadvisoryMODERATE2024-04-11

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2024-07-07
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-jjg7-2v4v-x38h

Frequently asked questions

What is CVE-2024-3651?

A vulnerability was identified in the kjd/idna library, specifically within the `idna.encode()` function, affecting version 3.6. The issue arises from the function's handling of crafted input strings, which can lead to quadratic complexity and consequently, a denial of service condition. This vulnerability is triggered by a crafted input that causes the `idna.encode()` function to process the input with considerable computational load, significantly increasing the processing time in a quadratic manner relative to the input size.

Is CVE-2024-3651 actively exploited?

Active exploitation of CVE-2024-3651 has not been confirmed. Its EPSS score was 1.4% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2024-3651?

CVE-2024-3651 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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