CVE-2019-15795 — python-apt
MEDIUMCVE-2019-15795 is a medium-severity (CVSS 4.7) Broken Cryptographic Algorithm vulnerability in python-apt. A fix is available for python-apt — see the affected versions and patch details below.
python-apt Flawed Package Integrity Check
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2019-15795 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
python-apt🐍python-apt🐍python-apt🐍python-apt🐍python-aptReal-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
python-apt only checks the MD5 sums of downloaded files in Version.fetch_binary() and Version.fetch_source() of apt/package.py in version 1.9.0ubuntu1 and earlier. This allows a man-in-the-middle attack which could potentially be used to install altered packages and has been fixed in versions 1.9.0ubuntu1.2, 1.6.5ubuntu0.1, 1.1.0~beta1ubuntu0.16.04.7, 0.9.3.5ubuntu3+esm2, and 0.8.3ubuntu7.5.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | python-apt | all versions | 0.8.3ubuntu7.5pip install --upgrade 'python-apt==0.8.3ubuntu7.5' |
| 🐍PyPI | python-apt | ≥ 0.9.0&&< 0.9.3.5ubuntu3 | 0.9.3.5ubuntu3pip install --upgrade 'python-apt==0.9.3.5ubuntu3' |
| 🐍PyPI | python-apt | ≥ 1.0.0&&< 1.1.0 | 1.1.0pip install --upgrade 'python-apt==1.1.0' |
| 🐍PyPI | python-apt | ≥ 1.2.0&&< 1.6.5ubuntu0.1 | 1.6.5ubuntu0.1pip install --upgrade 'python-apt==1.6.5ubuntu0.1' |
| 🐍PyPI | python-apt | ≥ 1.7.0&&< 1.9.0ubuntu1.2 | 1.9.0ubuntu1.2pip install --upgrade 'python-apt==1.9.0ubuntu1.2' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for python-apt, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update python-apt to 0.8.3ubuntu7.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-15795 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 O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2019-15795 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2019-15795. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2019-15795 in your dependencies?
O3 Security finds CVE-2019-15795 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.