CVE-2021-43820
Seafile Library Access Token Abuse
Description
Seafile is an open source cloud storage system. A sync token is used in Seafile file syncing protocol to authorize access to library data. To improve performance, the token is cached in memory in seaf-server. Upon receiving a token from sync client or SeaDrive client, the server checks whether the token exist in the cache. However, if the token exists in cache, the server doesn't check whether it's associated with the specific library in the URL. This vulnerability makes it possible to use any valid sync token to access data from any **known** library. Note that the attacker has to first find out the ID of a library which it has no access to. The library ID is a random UUID, which is not possible to be guessed. There are no workarounds for this issue.
INFO
Published Date :
Dec. 14, 2021, 7:15 p.m.
Last Modified :
Dec. 21, 2021, 5:17 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
5.2
Exploitability Score :
2.2
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-43820.
| URL | Resource |
|---|---|
| https://github.com/haiwen/seafile-server/pull/520 | Patch Third Party Advisory |
| https://github.com/haiwen/seafile-server/security/advisories/GHSA-m3wc-jv6r-hvv8 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-43820 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-43820 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Initial Analysis by [email protected]
Dec. 21, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:P/I:N/A:N) Added CVSS V3.1 NIST AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Changed Reference Type https://github.com/haiwen/seafile-server/pull/520 No Types Assigned https://github.com/haiwen/seafile-server/pull/520 Patch, Third Party Advisory Changed Reference Type https://github.com/haiwen/seafile-server/security/advisories/GHSA-m3wc-jv6r-hvv8 No Types Assigned https://github.com/haiwen/seafile-server/security/advisories/GHSA-m3wc-jv6r-hvv8 Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:seafile:seafile_server:*:*:*:*:community:*:*:* versions up to (excluding) 8.0.8 *cpe:2.3:a:seafile:seafile_server:*:*:*:*:professional:*:*:* versions up to (excluding) 8.0.15 *cpe:2.3:a:seafile:seafile_server:*:*:*:*:community:*:*:* versions from (including) 9.0.0 up to (excluding) 9.0.2
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-43820 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-43820
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.15 }} 0.01%
score
0.51748
percentile