Security readout for executives and security teams
Plain-English summary
CVE-2018-6346 can let a remote party cause a denial of service in Facebook Proxygen by sending invalid HTTP/2 priority settings involving a circular dependency. The issue affects Proxygen before v2018.12.31.00 and impacts availability, not data confidentiality or integrity.
Executive priority
Treat this as a high-priority availability risk for internet-facing or critical services using older Proxygen. Prioritize inventory confirmation and upgrade planning; urgency is lower where Proxygen is absent or not exposed to HTTP/2 traffic.
Technical view
Proxygen mishandled invalid HTTP/2 priority settings, specifically circular dependencies, leading to potential uncontrolled resource consumption or service disruption. CVSS 3.1 is 7.5 with network attack vector, low complexity, no privileges, no user interaction, unchanged scope, and high availability impact only.
Likely exposure
Exposure is most likely in services, gateways, or applications using Proxygen versions prior to v2018.12.31.00, especially where HTTP/2 traffic reaches Proxygen. The source bundle provides no CPEs, so teams must confirm dependency use from builds, SBOMs, and deployment inventories.
Exploitation context
The source bundle does not show CISA KEV listing or cited active exploitation. The CVSS vector indicates unauthenticated network reachability and low attack complexity, but available evidence only supports potential denial of service, not exploitation in the wild.
Researcher notes
Evidence is limited to the CVE description, CVSS metadata, and a vendor commit reference. The affected boundary is Proxygen before v2018.12.31.00. No public source in the bundle confirms exploitation, broader product impact, or alternate mitigations.
Mitigation direction
- Upgrade Proxygen to v2018.12.31.00 or later.
- Identify applications, proxies, or services that include Proxygen.
- Review the vendor commit before applying any backport.
- Monitor HTTP/2-facing services for abnormal availability degradation.
Validation and detection
- Confirm deployed Proxygen versions are v2018.12.31.00 or newer.
- Check SBOMs and build manifests for Proxygen use.
- Verify exposed services accept HTTP/2 traffic through Proxygen.
- Run regression tests for malformed HTTP/2 priority handling in a lab.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-400: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2018-6346 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/facebook/proxygen/commit/52cf331743ebd74194d6343a6c2ec52bb917c982CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.