CVE-2026-94440 Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart
Attackers can cause denial of service by bypassing memory limits during multipart form parsing in the Go standard library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-94440?
CVE-2026-94440 is a high-severity denial of service vulnerability in Go standard library mime/multipart, published on 8 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
Weakness: CWE-770
Which versions are affected by CVE-2026-94440?
2 open source packages ship an affected version, including golang and stdlib.
| Package | Affected | Fixed in |
|---|---|---|
golang Bitnami | All versions | 1.26.9, 1.27.2 |
stdlib Go | All versions | 1.26.9, 1.27.2 |
How do I fix CVE-2026-94440?
Upgrade golang to a fixed version for your release line: 1.26.9 or 1.27.2.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-94440 being exploited?
There is no known exploitation of CVE-2026-94440 in the wild and no public exploit code.
Sources
Also known as AZL-107463, AZL-107478, BELL-CVE-2026-94440, BIT-golang-2026-94440, CLEANSTART-2026-HO10487, CLEANSTART-2026-JC13614 and 2204 more.