How severe is CVE-2013-5123?

CVE-2013-5123 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2013-5123?

CVE-2013-5123 affects the following packages: pip (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2013-5123?

Update pip to 1.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2013-5123 is resolved across your whole dependency graph.

How do I detect CVE-2013-5123 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pip. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2013-5123 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2013-5123?

O3 pinpoints whether CVE-2013-5123 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2013-5123 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2013-5123, including 1 documented proof-of-concept exploit on Exploit-DB. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What type of vulnerability is CVE-2013-5123?

CVE-2013-5123 is classified as Improper Authentication (CWE-287). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2013-5123 published, and has it been updated?

CVE-2013-5123 was published on November 5, 2019 and was last updated on April 16, 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

CVE-2013-5123

MEDIUM

CVE-2013-5123 is a medium-severity (CVSS 5.9) Improper Authentication vulnerability in pip. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2013-5123 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Improper Authentication in pip

Also known asGHSA-c5h8-cq4v-cvfmPYSEC-2019-160

Published

Nov 5, 2019

Updated

Apr 16, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Blast Radius

1 pkg affected

🐍pip

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

The mirroring support (-M, --use-mirrors) in Python Pip before 1.5 uses insecure DNS querying and authenticity checks which allows attackers to perform man-in-the-middle attacks.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`pip`	all versions	1.5

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-24086webappsphp✓ Verified

phlyLabs phlyMail Lite 4.03.04 - 'go' Open Redirect

by LiquidWorm · Jan 13, 2013

Exploit-DB Source

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pip. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pip to 1.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2013-5123 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 pinpoints whether CVE-2013-5123 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2013-5123. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

The mirroring support (-M, --use-mirrors) in Python Pip before 1.5 uses insecure DNS querying and authenticity checks which allows attackers to perform man-in-the-middle attacks.

O3 Security · Impact-Aware SCA

Is CVE-2013-5123 in your dependencies?

O3 detects CVE-2013-5123 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works