What is CVE-2018-6343?

CVE-2018-6343 is a high-severity vulnerability in Facebook Proxygen, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2018-12-31.

How severe is CVE-2018-6343?

High severity. CVSS v3 base score is 7.5 out of 10.

NULL pointer dereference in Facebook Proxygen

CVE-2018-6343

Proxygen fails to validate that a secondary auth manager is set before dereferencing it. That can cause a denial of service issue when parsing a Certificate/CertificateRequest HTTP2 Frame over a fizz (TLS 1.3) transport. This issue affects Proxygen releases starting from v2018.10.29.00 until the fix in v2018.11.19.00.

Published 2018-12-31 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.008 (56.0th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Facebook Proxygen — versions v2018.11.19.00, v2018.10.29.00, unspecified

Weakness classification (CWE)

References

github.com/facebook/proxygen/commit/0600ebe59c3e82cd012def77ca9ca1918da74a71 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2018-6343?: CVE-2018-6343 is a high-severity vulnerability in Facebook Proxygen, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2018-12-31.
How severe is CVE-2018-6343?: High severity. CVSS v3 base score is 7.5 out of 10.