Cyber Resilience

CVE-2026-32283

DoS in Golang Go ≤ 1.25.9

Published
08 April 2026
Modified
12 August 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0062 47th percentile
Risk Priority 58 floored blend · peak EPSS

Summary

CVE-2026-32283 is a high-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Golang Go. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Denial of Service (T1498); ranked at the 47th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-10 (Concurrent Session Control) and SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-32283 is a denial-of-service vulnerability in the Go crypto/tls package. It occurs when one side of a TLS 1.3 connection sends multiple key update messages post-handshake within a single record, triggering a deadlock that leads to uncontrolled resource consumption. The issue is scored at CVSS 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) and maps to CWE-770 (Allocation of Resources Without Limits or Throttling). It exclusively affects TLS 1.3 implementations using the vulnerable Go crypto/tls code.

An unauthenticated remote attacker can exploit this by establishing a TLS 1.3 connection and transmitting a specially crafted record containing multiple key update messages after the handshake. This causes the affected peer to enter a deadlock state, exhausting CPU and memory resources, resulting in denial of service. Exploitation requires no user interaction or privileges and can target any Go application acting as a TLS server or client relying on the crypto/tls package for TLS 1.3.

Go advisories detail the fix in https://go.dev/cl/763767 and the issue tracker at https://go.dev/issue/78334, with an announcement on the golang-announce mailing list at https://groups.google.com/g/golang-announce/c/0uYbvbPZRWU. The vulnerability is tracked as GO-2026-4870 at https://pkg.go.dev/vuln/GO-2026-4870, recommending upgrades to patched Go versions that reject invalid multi-key-update records.

EU & UK References

Vulnerability Data

If one side of the TLS connection sends multiple key update messages post-handshake in a single record, the connection can deadlock, causing uncontrolled consumption of resources. This can lead to a denial of service. This only affects TLS 1.3.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1498 Network Denial of Service Impact
Adversaries may perform Network Denial of Service (DoS) attacks to degrade or block the availability of targeted resources to users.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
T1498.001 Direct Network Flood Impact
Adversaries may attempt to cause a denial of service (DoS) by directly sending a high-volume of network traffic to a target.
T1498.002 Reflection Amplification Impact
Adversaries may attempt to cause a denial of service (DoS) by reflecting a high-volume of network traffic to a target.
T1499.001 OS Exhaustion Flood Impact
Adversaries may launch a denial of service (DoS) attack targeting an endpoint's operating system (OS).
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-61728Same product: Golang Go
CVE-2025-61724Same product: Golang Go
CVE-2025-58185Same product: Golang Go
CVE-2023-24536Same product: Golang Go
CVE-2023-39322Same product: Golang Go
CVE-2026-32288Same product: Golang Go
CVE-2026-32280Same product: Golang Go
CVE-2025-61726Same product: Golang Go
CVE-2025-61723Same product: Golang Go
CVE-2026-39820Same product: Golang Go

Affected Assets

golang
go
≤ 1.25.9 · 1.26.0 — 1.26.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V15.4.4

Mitigating Controls (NIST 800-53 r5) AI

Directly enforces a hard limit on concurrent sessions, structurally preventing unbounded resource allocation.

Developer testing and evaluation can discover and correct multiple-lock flaws before deployment.

Requires explicit allocation of resources by priority or quota, directly stopping unlimited allocation.

Imposes a limit on consecutive invalid attempts, preventing one specific class of unbounded resource consumption.

Engineering principles for secure development can require correct use of synchronization primitives so multiple-lock errors are not introduced.

Reduces impact of resulting DoS events without preventing the underlying lack of allocation limits.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.IR-04 mostly match
degrades

Monitoring capacity and taking action to maintain availability directly reduces unchecked resource allocation.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly include coding standards and reviews that prevent improper multiple-lock synchronization errors.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Baseline comparison of CPU, memory and bandwidth usage helps surface uncontrolled resource allocations before they cause service degradation.

finds

Security testing in development can exercise locking scenarios and detect multiple-lock conditions before release.

prevents

Capacity projections and elasticity measures ensure that allocation requests are bounded and can be throttled, reducing the window in which an attacker can force unbounded resource reservations.

mitigates

Defining retention periods and deletion schedules for backup copies prevents indefinite accumulation of data on storage media without corresponding resource-management controls.

mitigates

Architectural redundancy and automatic failover limit the impact of an attacker who forces excessive allocations, because spare capacity can absorb the load until the primary instance recovers.

prevents

Secure development lifecycle practices can include concurrency and locking guidelines that reduce the risk of multiple-lock defects.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248552 OL 8 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. prevents CWE-770
  • V-248553 OL 8 must be configured so that all network connections associated with SSH traffic are terminated after 10 minutes of becoming unresponsive. prevents CWE-770
Oracle Linux 9 (2 rules)
  • V-271710 OL 9 must be configured so that all network connections associated with SSH traffic are terminated after 10 minutes of becoming unresponsive. prevents CWE-770
  • V-271709 OL 9 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. prevents CWE-770
RHEL 8 (1 rule)
  • V-230244 RHEL 8 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. prevents CWE-770

References