RCE in Bookstackapp Bookstack
CVE-2020-5256
BookStack before version 0.25.5 has a vulnerability where a user could upload PHP files through image upload functions, which would allow them to execute code on the host system remotely. They would then have the permissions of the PHP process. This most impacts scenarios where non-trusted users are given permission to upload images in any area of the application. The issue was addressed in a series of patches in versions 0.25.3, 0.25.4 and 0.25.5. Users should upgrade to at least v0.25.5 to avoid this vulnerability.
EPSS: 0.020 (78.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.9 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:L.
Affected products
- Bookstackapp Bookstack — versions < 0.25.5
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2020-5256?
- CVE-2020-5256 is a high-severity vulnerability in Bookstackapp Bookstack, classified under Eval Injection. CVSS score: 7.9/10. Published 2020-03-09.
- How severe is CVE-2020-5256?
- High severity. CVSS v3 base score is 7.9 out of 10.
- Is CVE-2020-5256 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.