How severe is CVE-2018-0505?

CVE-2018-0505 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2018-0505?

CVE-2018-0505 affects the following packages: mediawiki/core (Packagist), mediawiki/core (Packagist), mediawiki/core (Packagist), mediawiki/core (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2018-0505?

Update mediawiki/core to 1.27.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-0505 is resolved across your whole dependency graph.

How do I detect CVE-2018-0505 in my Packagist dependencies?

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

How do I mitigate CVE-2018-0505 if there is no patch (or I can't update yet)?

Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Is CVE-2018-0505 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2018-0505, including 1 in-the-wild exploitation observed on GitHub and other sources. 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 is the EPSS score for CVE-2018-0505?

CVE-2018-0505 has an EPSS (Exploit Prediction Scoring System) score of 2.0%, placing it in the 80th 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-2018-0505?

CVE-2018-0505 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-2018-0505 published, and has it been updated?

CVE-2018-0505 was published on October 4, 2018 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

Not in CISA KEV

MEDIUM severity

CVE-2018-0505 — core

MEDIUM

CVE-2018-0505 is a medium-severity (CVSS 6.5) Improper Authentication vulnerability in mediawiki/core. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for mediawiki/core — see the affected versions and patch details below.

Mediawiki BotPassword can bypass CentralAuth's account lock

Also known asGHSA-5c6w-f4w2-2grp

Published

Oct 4, 2018

Updated

Oct 24, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

1 known

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.0%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs80th percentile — riskier than 80% 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

4 pkgs affected

🐘mediawiki/core🐘mediawiki/core🐘mediawiki/core🐘mediawiki/core

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains a flaw where BotPasswords can bypass CentralAuth's account lock

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`mediawiki/core`	≥ 1.27.0&&< 1.27.5	1.27.5`composer require mediawiki/core:^1.27.5`
🐘Packagist	`mediawiki/core`	≥ 1.29.0&&< 1.29.3	1.29.3`composer require mediawiki/core:^1.29.3`
🐘Packagist	`mediawiki/core`	≥ 1.30.0&&< 1.30.1	1.30.1`composer require mediawiki/core:^1.30.1`
🐘Packagist	`mediawiki/core`	≥ 1.31.0&&< 1.31.1	1.31.1`composer require mediawiki/core:^1.31.1`

Affected Products

2 products · 5 configurations

debian linuxdebian

1 version

9.0

Application

mediawikimediawiki

≥ 1.31.0 && < 1.31.1

3 versions

1.27.51.29.31.30.1

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.

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains a flaw …

phabricator.wikimedia.orgNVDOct 2019

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mediawiki/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mediawiki/core to 1.27.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-0505 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

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 HatLow

Product	Fixed in	Advisory
Red Hat OpenShift Container Platform 3.10	`mediawiki-0:1.27.7-1.el7`	RHSA-2019:3238
Red Hat OpenShift Container Platform 3.11	`mediawiki-0:1.27.7-1.el7`	RHSA-2019:3142
Red Hat OpenShift Container Platform 3.9	`mediawiki123-0:1.23.17-1.el7`	RHSA-2019:3813

Frequently Asked Questions

Mediawiki 1.31 before 1.31.1, 1.30.1, 1.29.3 and 1.27.5 contains a flaw where BotPasswords can bypass CentralAuth's account lock

O3 Security · Impact-Aware SCA

Is CVE-2018-0505 in your dependencies?

Find it across Packagist, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

6.5/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Raw vector

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

CWE Classification

CWE-287Improper Authentication

Weaponization

No Nuclei template or Metasploit module yet. 1 public proof-of-concept reference is listed on this page.

OpenSSF Scorecard

Package health score

security-advisories

4.8/10

Maintained10/10

Code-Review10/10

Branch-Protection0/10

Assessed Nov 2, 2026

Timeline

Disclosed

Oct 4, 2018

First exploit

Oct 18, 2019

Last updated

Oct 24, 2026

Identifiers

CVE-2018-0505

GHSA-5c6w-f4w2-2grp

References

Advisorysecuritytracker.com Advisoryaccess.redhat.com · RHSA 2019:3142 Advisoryaccess.redhat.com · RHSA 2019:3238 Advisoryaccess.redhat.com · RHSA 2019:3813 Advisorydebian.org · dsa 4301 Advisorynvd.nist.gov · CVE 2018 0505 Fixlists.wikimedia.org Fixphabricator.wikimedia.org · T194605 Webgithub.com · CVE 2018 0505.yaml Packagegithub.com · mediawiki

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs affecting mediawiki/core are rated as high or higher (top: critical).

CVE-2023-45363CVE-2023-29141CVE-2019-12466CVE-2020-25815CVE-2019-12474CVE-2019-12471CVE-2019-12473CVE-2020-25814

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026

CVE-2018-0505 — core

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2018-0505 in your dependencies?