CVE-2024-21645 is a medium-severity (CVSS 5.3) CWE-74 vulnerability in pyload-ng. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for pyload-ng — see the affected versions and patch details below.
pyLoad Log Injection
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-21645.
EPSS Exploitation Probability
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
pyload-ngReal-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
Summary
A log injection vulnerability was identified in pyload. This vulnerability allows any unauthenticated actor to inject arbitrary messages into the logs gathered by pyload.
Details
pyload will generate a log entry when attempting to sign in with faulty credentials. This entry will be in the form of Login failed for user 'USERNAME'. However, when supplied with a username containing a newline, this newline is not properly escaped. Newlines are also the delimiter between log entries. This allows the attacker to inject new log entries into the log file.
PoC
Run pyload in the default configuration by running the following command
pyload
We can now sign in as the pyload user and view the logs at http://localhost:8000/logs.
Any unauthenticated attacker can now make the following request to inject arbitrary logs.
curl 'http://localhost:8000/login?next=http://localhost:8000/' -X POST -H 'Content-Type: application/x-www-form-urlencoded' --data-raw $'do=login&username=wrong\'%0a[2024-01-05 02:49:19] HACKER PinkDraconian THIS ENTRY HAS BEEN INJECTED&password=wrong&submit=Login'
If we now were to look at the logs again, we see that the entry has successfully been injected.
Impact
Forged or otherwise, corrupted log files can be used to cover an attacker’s tracks or even to implicate another party in the commission of a malicious act.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pyload-ng | all versions | 0.5.0b3.dev77pip install --upgrade 'pyload-ng==0.5.0b3.dev77' |
Affected Products
pyloadpyloadResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pyload-ng, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pyload-ng to 0.5.0b3.dev77 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-21645 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How to detect CVE-2024-21645
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2024-21645 -u https://target- Template
- pyload - Log Injection
- Severity
- medium
- Impact
- Forged or otherwise, corrupted log files can be used to cover an attacker's tracks or even to implicate another party in the commission of a malicious act.
- Remediation
- Apply the latest security patches and updates from the vendor to address this vulnerability.
Template by ProjectDiscovery nuclei-templates (isacaya), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2024-21645 in your dependencies?
Find it across PyPI, including transitive dependencies.