CVE-2023-49295 | quic-go's path validation mechanism can cause denial of service

quic-go is an implementation of the QUIC protocol (RFC 9000, RFC 9001, RFC 9002) in Go. An attacker can cause its peer to run out of memory sending a large number of PATH_CHALLENGE frames. The receiver is supposed to respond to each PATH_CHALLENGE frame with a PATH_RESPONSE frame. The attacker can prevent the receiver from sending out (the vast majority of) these PATH_RESPONSE frames by collapsing the peers congestion window (by selectively acknowledging received packets) and by manipulating the peer's RTT estimate. This vulnerability has been patched in versions 0.37.7, 0.38.2 and 0.39.4.

Published: 2024-01-10 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-49295 is rated Moderate Risk (54.8/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.77%). Review affected assets and schedule remediation.

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-2023-49295

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 2026-03-22 1.44% 1.77% +0.33%
2 2026-01-28 1.06% 1.44% +0.37%
3 2026-01-18 — 1.06% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-49295

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 4.7 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H 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:L)
A normal user session is enough; they don’t have to be admin.
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:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2023-49295

GitHub Security Advisory for CVE-2023-49295

GHSA-ppxx-5m9h-6vxf · Severity: medium · Ecosystem: go — quic-go's path validation mechanism can be exploited to cause denial of service

OS Trackers for CVE-2023-49295

vendor priority summary link
debian not yet assigned CVE-2023-49295 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): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2023-49295
redhat medium — https://access.redhat.com/security/cve/CVE-2023-49295
suse medium — https://www.suse.com/security/cve/CVE-2023-49295/
ubuntu medium CVE-2023-49295 medium priority: Ubuntu including 1 source packages (golang-github-lucas-clemente-quic-go), 12 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 7, needs-triage 4, DNE 1. https://ubuntu.com/security/CVE-2023-49295

Affected software / configurations for CVE-2023-49295

Vendor Product Version Raw CPE
quic-go_project quic-go < 0.37.7 cpe:2.3:a:quic-go_project:quic-go:*:*:*:*:*:*:*:*
quic-go_project quic-go >= 0.38.0, < 0.38.2 cpe:2.3:a:quic-go_project:quic-go:*:*:*:*:*:*:*:*
quic-go_project quic-go >= 0.39.0, < 0.39.4 cpe:2.3:a:quic-go_project:quic-go:*:*:*:*:*:*:*:*
quic-go_project quic-go 0.40.0 cpe:2.3:a:quic-go_project:quic-go:0.40.0:*:*:*:*:*:*:*

References for CVE-2023-49295

URL Tags
https://github.com/quic-go/quic-go/commit/17fc98c2d81dbe685c19702dc694a9d606ac56dc Patch
https://github.com/quic-go/quic-go/commit/21609ddfeff93668c7625a85eb09f1541fdad965 Patch
https://github.com/quic-go/quic-go/commit/3a9c18bcd27a01c551ac9bf8bd2b4bded77c189a Patch
https://github.com/quic-go/quic-go/commit/554d543b50b917369fb1394cc5396d928166cf49 Patch
https://github.com/quic-go/quic-go/commit/6cc3d58935426191296171a6c0d1ee965e10534e Patch
https://github.com/quic-go/quic-go/commit/9aaefe19fc3dc8c8917cc87e6128bb56d9e9e6cc Patch
https://github.com/quic-go/quic-go/commit/a0ffa757499913f7be69aa78f573a6aee3430ae4 Patch
https://github.com/quic-go/quic-go/commit/d7aa627ebde91cf799ada2a07443faa9b1e5abb8 Patch
https://github.com/quic-go/quic-go/security/advisories/GHSA-ppxx-5m9h-6vxf Vendor Advisory
https://lists.fedoraproject.org/archives/list/[email protected]/message/G5RSHDTVMYAIGYVVFGKTMFHAZJMA3EVV/
https://lists.fedoraproject.org/archives/list/[email protected]/message/ZE7IOKXX5AATU2WR3V76X5Y3A44QAATG/
cvelogic Threat Intelligence