CVE-2026-54332 GoPacket's sFlow ExtendedGatewayFlow decoder: unbounded attacker-controlled allocation (104-byte UDP datagram -> up to 16 GiB make) -> unauthenticated remote DoS

Medium 6.9 Published 28 Jul 2026 Updated 28 Jul 2026

An attacker can cause a denial of service by sending a small UDP datagram that triggers excessive memory allocation in the sFlow decoder.

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

What is CVE-2026-54332?

CVE-2026-54332 is a medium-severity denial of service vulnerability in gopacket, published on 28 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

gopacket provides packet processing capabilities for Go. In version 1.6.0 and earlier, the sFlow ExtendedGatewayFlow decoder in layers/sflow.go reads an attacker-controlled 32-bit community count and AS path member count and sizes a slice allocation from those counts without bounding them against the bytes remaining in the datagram, so a 104-byte UDP datagram can drive an allocation of up to 16 GiB and cause an unauthenticated remote denial of service. This issue is fixed in version 1.6.1.

Weakness: CWE-770

Which versions are affected by CVE-2026-54332?

3 open source packages ship an affected version, including github.com/gopacket/gopacket. It affects 1 product.

Package	Affected	Fixed in
`github.com/gopacket/gopacket` Go	All versions	`1.6.1`
`github.com/gopacket/gopacket` Go	All versions	`1.6.1`
`github.com/gopacket/gopacket` Go	All versions	`1.6.1`

Products include Gopacket Gopacket.

How do I fix CVE-2026-54332?

Upgrade github.com/gopacket/gopacket to 1.6.1 or later.

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-2026-54332 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54332 exists.

CVE-2026-54345 GoPacket's Diameter AVP decoder: uint32 underflow on vendor header size leads to unbounded ~4 GiB allocation (unauthenticated remote DoS) Medium 6.9

Sources

Also known as AZL-94323, CLEANSTART-2026-BH05638, DEBIAN-CVE-2026-54332, GHSA-g6v3-7xmc-w563, GO-2026-6122, MINI-2hgp-c865-m2g5 and 20 more.