CVE-2023-6193

mediumpriority · track · 21EPSS 0.008 · 55 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.76% (55th) EPSS

CVSS 5.3 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

quiche v. 0.15.0 through 0.19.0 was discovered to be vulnerable to unbounded queuing of path validation messages, which could lead to excessive resource consumption. QUIC path validation (RFC 9000 Section 8.2) requires that the recipient of a PATH_CHALLENGE frame responds by sending a PATH_RESPONSE. An unauthenticated remote attacker can exploit the vulnerability by sending PATH_CHALLENGE frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that PATH_RESPONSE frames can only be sent at the slower rate than they are received; leading to storage of path validation data in an unbounded queue. Quiche versions greater than 0.19.0 address this problem.

cvss

Technical severity, 0–10. One row per scoring source.

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · cna@cloudflare.comexploitability 3.9 · impact 1.4

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · OSV

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US

affected products (3)

Products and version ranges known to be affected.

Cloudflare quiche≤ 0.15.0 ≤0.19.0enisa_euvdEU
cloudflare quiche0.15.0 → 0.19.0nvdUScpe:2.3:a:cloudflare:quiche:*:*:*:*:*:*:*:*
crates.io quiche0.15.0 → 0.19.1osvUSpkg:cargo/quiche

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-w3vp-jw9m-f9pmUnbounded queuing of path validation messages in cloudflare-quiche2023-12-13ghsa · osvUS
### Impact quiche v. 0.15.0 through 0.19.0 was discovered to be vulnerable to unbounded queuing of path validation messages, which could lead to excessive resource consumption. QUIC path validation ([RFC 9000 Section 8.2](https://datatracker.ietf.org/doc/html/rfc9000#section-8.2)) requires that the recipient of a PATH_CHALLENGE frame responds by sending a PATH_RESPONSE. An unauthenticated remote attacker can exploit the vulnerability by sending PATH_CHALLENGE frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that PATH_RESPONSE frames can only be sent at the slower rate than they are received, leading to storage of path validation data in an unbounded queue. ### Patches Quiche versions greater than 0.19.0 address this problem. ### References [CVE-2023-6193](https://www.cve.org/CVERecord?id=CVE-2023-6193) [RFC 9000 Section 8.2](https://datatracker.ietf.org/doc/html/rfc9000#section-8.2)

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2023-12-12modified 2026-06-17

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+9613 more

references (7)

External citations — patches, advisories, analysis.

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