CVE-2020-15275 malicious SVG attachment causing stored XSS vulnerability in MoinMoin

What is CVE-2020-15275?

CVE-2020-15275 is a high-severity cross-site scripting vulnerability in moinwiki moin-1.9, published on 11 Nov 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

Official description

MoinMoin is a wiki engine. In MoinMoin before version 1.9.11, an attacker with write permissions can upload an SVG file that contains malicious javascript. This javascript will be executed in a user's browser when the user is viewing that SVG file on the wiki. Users are strongly advised to upgrade to a patched version. MoinMoin Wiki 1.9.11 has the necessary fixes and also contains other important fixes.

Weakness: CWE-79

Which versions are affected by CVE-2020-15275?

3 open source packages ship an affected version, including moin. It affects 1 product.

Products include Moinmo Moinmoin.

How do I fix CVE-2020-15275?

Upgrade moin to 1.9.11 or later.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2020-15275 being exploited?

There is no known exploitation of CVE-2020-15275 in the wild and no public exploit code.

Other vulnerabilities in moinwiki moin-1.9

• CVE-2009-4762 MoinMoin Improper Access Control vulnerability High 7.5
• CVE-2010-0669 MoinMoin improper sanitizes user profiles High 7.5
• CVE-2010-0717 MoinMoin has improper default configuration High 7.5
• CVE-2010-0668 MoinMoin has multiple vulnerabilities related to superuser list, xmlrpc and OpenID configuration Medium 6.8
• CVE-2008-6603 MoinMoin Access Restrictions Bypassed due to improper ACL enforcement Medium 6.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-4q96-6xhq-ff43, PYSEC-2020-241, UBUNTU-CVE-2020-15275.