CVE-2025-59350 Timing attacks against Proxy’s basic authentication are possible

Low 2.7 Published 17 Sep 2025 Updated 18 Sep 2025

Attackers can exploit timing side-channels in Dragonfly's Proxy authentication to guess passwords character-by-character, potentially bypassing access controls.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2025-59350?

CVE-2025-59350 is a low-severity vulnerability in dragonflyoss dragonfly, published on 17 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Dragonfly is an open source P2P-based file distribution and image acceleration system. Prior to 2.1.0, the access control mechanism for the Proxy feature uses simple string comparisons and is therefore vulnerable to timing attacks. An attacker may try to guess the password one character at a time by sending all possible characters to a vulnerable mechanism and measuring the comparison instruction’s execution times. This vulnerability is fixed in 2.1.0.

Weakness: CWE-208

Which versions are affected by CVE-2025-59350?

6 open source packages ship an affected version, including github.com/dragonflyoss/dragonfly and d7y.io/dragonfly/v2. It affects 1 product.

Package	Affected	Fixed in
`github.com/dragonflyoss/dragonfly` Go	All versions	None
`github.com/dragonflyoss/dragonfly` Go	All versions	`2.1.0`
`github.com/dragonflyoss/dragonfly` Go	All versions	`2.1.0`
`d7y.io/dragonfly/v2` Go	All versions	`2.1.0`
`d7y.io/dragonfly/v2` Go	All versions	`2.1.0`
`d7y.io/dragonfly/v2` Go	All versions	`2.1.0`

Products include Linuxfoundation Dragonfly.

How do I fix CVE-2025-59350?

Upgrade github.com/dragonflyoss/dragonfly to 2.1.0 or later.

Is CVE-2025-59350 being exploited?

There is no known exploitation of CVE-2025-59350 in the wild and no public exploit code.

Sources

Also known as GHSA-c2fc-9q9c-5486, GO-2025-3972.