Is CVE-2026-77609 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-77609 being exploited in the wild.

How severe is CVE-2026-77609?

Medium severity, with a CVSS score of 6.1, published 18 September 2026.

Which products and versions are affected?

mediawiki/semantic-media-wiki (Packagist) <= 7.1.0, ECOSYSTEM:introduced=0,fixed=7.2.0; Semantic MediaWiki <= 7.1.0.

Is there a fix for CVE-2026-77609?

Yes. mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-77609 attacked?

It is attacked over the network.

Am I affected by CVE-2026-77609?

Check whether you run mediawiki/semantic-media-wiki (Packagist) or Semantic MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-77609: Semantic MediaWiki open redirect in Special:URIResolver

Q: Is there a fix for CVE-2026-77609?

Yes. mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-77609 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-77609?

Check whether you run mediawiki/semantic-media-wiki (Packagist) or Semantic MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-77609 · Severity: medium · CVSS 6.1 · Published 2026-09-18

Semantic MediaWiki is a semantic layer for MediaWiki that extends its capabilities with structured data. The Special:URIResolver page contains an open redirect vulnerability that allows attackers to craft URLs appearing to originate from a trusted wiki but actually redirecting to attacker-controlled hosts. This can be used for phishing attacks against wiki users and staff.

Technologies: mediawiki/semantic-media-wiki (Packagist), Semantic MediaWiki. Vendors: Packagist, Semantic MediaWiki.

Quick answers

Is CVE-2026-77609 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-77609 being exploited in the wild.
How severe is CVE-2026-77609?: Medium severity, with a CVSS score of 6.1, published 18 September 2026.
Which products and versions are affected?: mediawiki/semantic-media-wiki (Packagist) <= 7.1.0, ECOSYSTEM:introduced=0,fixed=7.2.0; Semantic MediaWiki <= 7.1.0.
Is there a fix for CVE-2026-77609?: Yes. mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-77609 attacked?: It is attacked over the network.
Am I affected by CVE-2026-77609?: Check whether you run mediawiki/semantic-media-wiki (Packagist) or Semantic MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later
```
composer require mediawiki/semantic-media-wiki:^7.2.0
```

Technical details

The vulnerability is an open redirect (CWE-601) in the Special:URIResolver page. The vulnerable component processes user-controlled subpage parameters and resolves them to MediaWiki titles, then issues an HTTP 303 redirect to the resolved URL without validating the target host. An attacker can craft a URL using interwiki prefixes (e.g., mw-3AFoo decoding to mw:Foo) or embed credentials (user:pass@host) to redirect to off-host destinations. The attack requires user interaction (clicking the link) and is network-accessible without authentication. The patch validates the resolved target URL and host matches against the current host before issuing the redirect.

Affected products

Semantic MediaWiki Semantic MediaWiki <= 7.1.0

Identifiers

CVE-2026-77609
GHSA-hw3m-8j5x-94ff

Timeline

2026-09-18: disclosed
2026-09-18: patched: Version 7.2.0 patches the vulnerability

References

https://api.github.com/users/krabina

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