Insert tag injection in the Contao login module

published 2019-12-17 6 y ago modified 2026-06-17 4 mo ago also GHSA-jc43-qrrp-98f5 , EUVD-2019-0796

cvss: 5.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits: 0; none known

Contao 4.8.4 and 4.8.5 has Improper Encoding or Escaping of Output. It is possible to inject insert tags into the login module which will be replaced when the page is rendered.

Patch / fix

fixed in 2

packagist contao/core-bundle 4.8.6
packagist contao/contao 4.8.6

Exploit prediction

0.82% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N
GitHub	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
packagist	contao/core-bundle	>=4.8.4, <4.8.6	4.8.6
packagist	contao/contao	>=4.8.4, <4.8.6	4.8.6

Classification

Weakness

CWE-116 Improper Encoding or Escaping of Output

References

contao.org /en/news.html
vendor-advisory
contao.org /en/security-advisories/insert-tag-injection-in-the-login-module.html
web, vendor-advisory
github.com /contao/contao/security/advisories/GHSA-jc43-qrrp-98f5
web
nvd.nist.gov /vuln/detail/CVE-2019-19714
advisory
github.com /FriendsOfPHP/security-advisories/blob/master/contao/contao/CVE-2019-19714.yaml
web
github.com /FriendsOfPHP/security-advisories/blob/master/contao/core-bundle/CVE-2019-19714.yaml
web
github.com /contao/contao
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary