CVE-2017-17688 json
The OpenPGP specification allows a Cipher Feedback Mode (CFB) malleability-gadget attack that can indirectly lead to plaintext exfiltration…
published 2018-05-16 8 y ago modified 2026-06-17 4 mo ago also EUVD-2017-8845
- cvss
- 5.9
- version 3.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 5.4%
- EPSS 5.4% chance of exploitation in 30 days, percentile 92%
- public exploits
- 0
- none known
Summary
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
Patch / fix
- enigmail Debian 11 2:2.0.6.1-4
debian advisories DEBIAN-CVE-2017-17688
- enigmail openSUSE Tumbleweed 2.2.4-1.4
- enigmail Package Hub 12 2.0.4-9.1
opensuse advisories openSUSE-SU-2024:10736-1openSUSE-SU-2018:1329-1openSUSE-SU-2018:1330-1
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2017-17688 updated cvss 5.3
OpenPGP: CFB gadget attacks allows to exfiltrate plaintext out of encrypted emails
-
Red Hat Enterprise Linux 6 kdepim, kdepim-libs, thunderbird Red Hat Enterprise Linux 7 kdepim, kdepim-libs, thunderbird Red Hat Enterprise Linux 8 thunderbirdnot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
5.44% chance of exploitation in the next 30 days, higher than 92% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- efail.de https://efail.de referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 5.9 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:P/I:N/A:N |
References
-
efail.de
exploit, mitigation, third-party-advisory
-
protonmail.com
/blog/pgp-vulnerability-efail
issue-tracking, third-party-advisory
-
news.ycombinator.com
/item?id=17066419
issue-tracking, third-party-advisory
-
patreon.com
/posts/cybersecurity-15-18814817
issue-tracking, third-party-advisory
-
flaked.sockpuppet.org
/2018/05/16/a-unified-timeline.html
third-party-advisory
-
securityfocus.com
/bid/104162
vdb-entry, third-party-advisory
-
lists.gnupg.org
/pipermail/gnupg-users/2018-May/060334.html
third-party-advisory
-
twitter.com
/matthew_d_green/status/995996706457243648
third-party-advisory
-
synology.com
/support/security/Synology_SA_18_22
third-party-advisory
-
securitytracker.com
/id/1040904
vdb-entry, third-party-advisory
Sources
- CVE List CVE-2017-17688
- NVD CVE-2017-17688
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.