CVE-2026-70657 Copyparty: file/dirkey confusion
Attackers can use a valid file key to gain read access to the containing directory when both file and directory key features are enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-70657?
CVE-2026-70657 is a medium-severity authentication bypass vulnerability in 9001 copyparty, published on 18 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Copyparty is a portable file server. Prior to 1.20.17, copyparty volumes with the dk or dks directory-key flag combined with the fk or fka file-key flag can convert a valid file key into a directory key, granting read access to the containing folder. This vulnerability was only reachable if both types of keys (filekeys and dirkeys) were manually enabled in the volume flags simultaneously. This issue is fixed in version 1.20.17.
Weakness: CWE-863
Which versions are affected by CVE-2026-70657?
3 open source packages ship an affected version, including copyparty.
| Package | Affected | Fixed in |
|---|---|---|
copyparty PyPI | All versions | 1.20.17 |
copyparty PyPI | All versions | 1.20.17 |
copyparty PyPI | All versions | 1.20.17 |
How do I fix CVE-2026-70657?
Upgrade copyparty to 1.20.17 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-70657 being exploited?
There is no known exploitation of CVE-2026-70657 in the wild and no public exploit code.
Sources
Also known as GHSA-x5pq-m9p8-f4vx, PYSEC-2026-3660.