CVE-2021-43820
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering.
- Exploit odds
- 1.0% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 1.0% in the next 30 days (EPSS).
- Severity: 7.4 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 1.0% · EPSS, next 30 days
- Weakness
- CWE-639 · Insecure direct object reference
- Record status
- Modified
Affected
- Seafile Server < 8.0.8
- Seafile Server < 8.0.15
- Seafile Server < 9.0.2
Attack profile CVSS 3.1 · 7.4
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-43820.md and follow it. Check whether this project is affected by CVE-2021-43820. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/haiwen/seafile-server/pull/520
- https://github.com/haiwen/seafile-server/security/advisories/GHSA-m3wc-jv6r-hvv8
- https://github.com/haiwen/seafile-server/pull/520
- https://github.com/haiwen/seafile-server/security/advisories/GHSA-m3wc-jv6r-hvv8