CVE-2021-3131

HIGH 7.5CVE-2021-3131 · Published 13/01/2021 · updated 17/06/2026

In short

CVE-2021-3131 is a HIGH (CVSS 7.5) vulnerability affecting 1c (1c).
Chance of exploitation in the next 30 days (EPSS): 0.97%, higher than 62.2% of all vulnerabilities.
Fix: update to 8.3.17.1851 or later.

Package	Affected versions	Patched versions
1c 1c	`≥ 8.0, < 8.3.17.1851`	`8.3.17.1851`

The Web server in 1C:Enterprise 8 before 8.3.17.1851 sends base64 encoded credentials in the creds URL parameter.

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