CVE-2025-61724 Excessive CPU consumption in Reader.ReadResponse in net/textproto

What is CVE-2025-61724?

CVE-2025-61724 is a medium-severity denial of service vulnerability in Golang Go, published on 29 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The Reader.ReadResponse function constructs a response string through repeated string concatenation of lines. When the number of lines in a response is large, this can cause excessive CPU consumption.

Weakness: CWE-770

Which versions are affected by CVE-2025-61724?

2 open source packages ship an affected version, including golang and stdlib. It affects 1 product.

Products include Golang Go.

How do I fix CVE-2025-61724?

Upgrade golang to a fixed version for your release line: 1.24.8 or 1.25.2.

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-2025-61724 being exploited?

There is no known exploitation of CVE-2025-61724 in the wild and no public exploit code.

Other vulnerabilities in Golang Go

• CVE-2020-0601 Microsoft Windows CryptoAPI Spoofing Exploited High 8.1
• CVE-2026-27143 Missing bound checks can lead to memory corruption in safe Go in cmd/compile Critical 9.8
• CVE-2024-24790 Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip Critical 9.8
• CVE-2023-39320 Arbitrary code execution via go.mod toolchain directive in cmd/go Critical 9.8
• CVE-2023-24540 Improper handling of JavaScript whitespace in html/template Critical 9.8

All Golang Go vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-69164, AZL-69257, AZL-78921, AZL-98850, BELL-CVE-2025-61724, BIT-golang-2025-61724 and 284 more.