CVE-2026-77166

LOW
Published Sep 21, 2026 Modified Sep 22, 2026 CWE-840

Description

The emoji field in the page emoji update endpoint does not properly validate user input. By injecting long text and line breaks, the sidebar layout becomes broken and can hide other items.

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CVSS v3.1 Score

2.4
LOW
CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:L/A:N

EPSS — Exploit Prediction

0.0028
Probability of exploitation
0.20%
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-840 CWE-840

References

Frequently Asked Questions

What is CVE-2026-77166? +
The emoji field in the page emoji update endpoint does not properly validate user input. By injecting long text and line breaks, the sidebar layout becomes broken and can hide other items. It has a CVSS v3.1 base score of 2.4 (LOW).
How severe is CVE-2026-77166? +
CVE-2026-77166 has a CVSS v3.1 score of 2.4 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0028, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-77166? +
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.

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