CVE-2026-55442

MEDIUM
Published Oct 23, 2026 Modified Oct 29, 2026 CWE-20 CWE-116

Description

The Goobi viewer is a web application that allows digitised material to be displayed in a web browser. From version 23.03 to before version 26.05, SolrTools.cleanUpQuery() strips Solr local-parameter syntax ({!...}) from user-supplied query strings before they reach Solr. Its regex can be bypassed by wrapping the local parameter in a second pair of curly braces ({{!...}}): the outer braces are stripped, the inner {!...} survives intact, and a valid Solr local parameter is forwarded. The flaw is in the shared sanitizer, so it affects any endpoint that routes user input through cleanUpQuery. The double-brace bypass applies from v23.10 (the greedy \{(.+)\} regex); a related bare-!join rewrap path is present. This issue has been patched in version 26.05.

Is your site exposed to CVE-2026-55442?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.3
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0026
Probability of exploitation
0.18%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-20 Improper Input Validation
CWE-116 CWE-116

References

Frequently Asked Questions

What is CVE-2026-55442? +
The Goobi viewer is a web application that allows digitised material to be displayed in a web browser. From version 23.03 to before version 26.05, SolrTools.cleanUpQuery() strips Solr local-parameter syntax ({!...}) from user-supplied query strings before they reach Solr. Its regex can be bypassed by wrapping the local parameter in a second pair of curly braces ({{!...}}): the outer braces are stripped, the inner {!...} survives intact, and a valid Solr local parameter is forwarded. The flaw is in the shared sanitizer, so it affects any endpoint that routes user input through cleanUpQuery. The double-brace bypass applies from v23.10 (the greedy \{(.+)\} regex); a related bare-!join rewrap path is present. This issue has been patched in version 26.05. It has a CVSS v3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-55442? +
CVE-2026-55442 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-55442? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-55442 — free, no signup required.