CVE-2025-64702 | quic-go HTTP/3 QPACK Header Expansion DoS

quic-go is an implementation of the QUIC protocol in Go. Versions 0.56.0 and below are vulnerable to excessive memory allocation through quic-go's HTTP/3 client and server implementations by sending a QPACK-encoded HEADERS frame that decodes into a large header field section (many unique header names and/or large values). The implementation builds an http.Header (used on the http.Request and http.Response, respectively), while only enforcing limits on the size of the (QPACK-compressed) HEADERS frame, but not on the decoded header, leading to memory exhaustion. This issue is fixed in version 0.57.0.

Published: 2025-12-11 Last update: 2026-02-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-64702 is rated Low Risk (22.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-64702

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-06 0.05% 0.01% -0.04%
2 2025-12-17 0.04% 0.05% +0.01%
3 2025-12-12 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-64702

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2025-64702

GitHub Security Advisory for CVE-2025-64702

GHSA-g754-hx8w-x2g6 · Severity: medium · Ecosystem: go — quic-go HTTP/3 QPACK Header Expansion DoS

OS Trackers for CVE-2025-64702

vendor priority summary link
debian not yet assigned CVE-2025-64702 not yet assigned priority: Debian including 1 source packages (golang-github-lucas-clemente-quic-go), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2025-64702
redhat medium — https://access.redhat.com/security/cve/CVE-2025-64702
suse medium CVE-2025-64702 severity moderate: SUSE including 15 source package names (teleport-17.7.13-1.1, teleport-bash-completion-17.7.13-1.1, …), 15 product×package rows across 2 product lines (openSUSE Leap 16.0, openSUSE Tumbleweed): Fixed 15. https://www.suse.com/security/cve/CVE-2025-64702/
ubuntu medium CVE-2025-64702 medium priority: Ubuntu including 1 source packages (golang-github-lucas-clemente-quic-go), 5 status rows across 5 suites (jammy, noble, plucky, questing, upstream): needs-triage 4, ignored 1. https://ubuntu.com/security/CVE-2025-64702

Affected software / configurations for CVE-2025-64702

Vendor Product Version Raw CPE
quic-go_project quic-go < 0.57.0 cpe:2.3:a:quic-go_project:quic-go:*:*:*:*:*:*:*:*

References for CVE-2025-64702

cvelogic Threat Intelligence