How severe is CVE-2015-5963?

CVE-2015-5963 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2015-5963?

CVE-2015-5963 affects the following packages: django (PyPI), django (PyPI), django (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2015-5963?

Update django to 1.8.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2015-5963 is resolved across your whole dependency graph.

How do I detect CVE-2015-5963 in my PyPI dependencies?

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

How do I mitigate CVE-2015-5963 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-2015-5963 actively exploited in the wild?

No public exploit code has been indexed for CVE-2015-5963 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-2015-5963?

CVE-2015-5963 has an EPSS (Exploit Prediction Scoring System) score of 5.2%, placing it in the 92th 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-2015-5963?

CVE-2015-5963 is classified as CWE-399 (CWE-399). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2015-5963 published, and has it been updated?

CVE-2015-5963 was published on August 24, 2015 and was last updated on July 15, 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

HIGH severity

CVE-2015-5963 — django

HIGHFix: django/django@2eb86b0

CVE-2015-5963 is a high-severity (CVSS 7.5) CWE-399 vulnerability in django. A fix is available for django — see the affected versions and patch details below.

Django denial of service via empty session record creation

Also known asGHSA-pgxh-wfw4-jx2vPYSEC-2015-22

Published

Aug 24, 2015

Updated

Jul 15, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

Exploitation data as of Nov 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

5.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs92th percentile — riskier than 92% 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

3 pkgs affected

🐍django🐍django🐍django

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

contrib.sessions.middleware.SessionMiddleware in Django 1.8.x before 1.8.4, 1.7.x before 1.7.10, 1.4.x before 1.4.22, and possibly other versions allows remote attackers to cause a denial of service (session store consumption or session record removal) via a large number of requests to contrib.auth.views.logout, which triggers the creation of an empty session record.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`django`	≥ 1.8&&< 1.8.4	1.8.4`pip install --upgrade 'django==1.8.4'`
🐍PyPI	`django`	≥ 1.7&&< 1.7.10	1.7.10`pip install --upgrade 'django==1.7.10'`
🐍PyPI	`django`	≥ 1.4&&< 1.4.22	1.4.22`pip install --upgrade 'django==1.4.22'`

Affected Products

3 products · 43 configurations

ubuntu linuxcanonical

3 versions

12.0414.0415.04

Application

djangodjangoproject

33 versions

1.41.4.11.4.21.4.41.4.51.4.61.4.71.4.81.4.91.4.101.4.111.4.12

solarisoracle

1 version

11.3

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for django, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update django to 1.8.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2015-5963 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

Product	Fixed in	Advisory
Red Hat Enterprise Linux OpenStack Platform 5.0 (Icehouse) for RHEL 6	`python-django-0:1.6.11-3.el6ost`	RHSA-2015:1766
Red Hat Enterprise Linux OpenStack Platform 5.0 (Icehouse) for RHEL 7	`python-django-0:1.6.11-3.el7ost`	RHSA-2015:1767
Red Hat Enterprise Linux OpenStack Platform 6.0 (Juno) for RHEL 7	`python-django-0:1.6.11-3.el7ost`	RHSA-2015:1894
Red Hat Enterprise Linux OpenStack Platform 7.0 (Kilo) for RHEL 7	`python-django-0:1.8.4-1.el7`	RHSA-2015:1876

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2015-5963 in your dependencies?

Find it across PyPI, including transitive dependencies.

Scan my dependencies How O3 SCA works