How severe is CVE-2017-17688?

CVE-2017-17688 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2017-17688 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-17688?

CVE-2017-17688 primarily affects Apple Mail. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-17688?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-17688 published?

CVE-2017-17688 was published on 2018-05-16 and last updated on 2026-06-17.

CVE-2017-17688

CVE-2017-17688 is a medium-severity vulnerability in Apple Mail with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Apple Mail
Published: 2018-05-16
Last modified: 2026-06-17

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

Frequently asked questions

What is CVE-2017-17688?: 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
How severe is CVE-2017-17688?: CVE-2017-17688 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2017-17688 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-17688?: CVE-2017-17688 primarily affects Apple Mail. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-17688?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-17688 published?: CVE-2017-17688 was published on 2018-05-16 and last updated on 2026-06-17.

References

Affected products (12)

cpe:2.3:a:apple:mail:-:*:*:*:*:*:*:*
cpe:2.3:a:apple:mail:-:*:*:*:*:iphone_os:*:*
cpe:2.3:a:bloop:airmail:-:*:*:*:*:*:*:*
cpe:2.3:a:emclient:emclient:-:*:*:*:*:*:*:*
cpe:2.3:a:flipdogsolutions:maildroid:-:*:*:*:*:*:*:*
cpe:2.3:a:freron:mailmate:-:*:*:*:*:*:*:*
cpe:2.3:a:horde:horde_imp:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:outlook:2007:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:-:*:*:*:*:*:*:*
cpe:2.3:a:postbox-inc:postbox:-:*:*:*:*:*:*:*
cpe:2.3:a:r2mail2:r2mail2:-:*:*:*:*:*:*:*
cpe:2.3:a:roundcube:webmail:-:*:*:*:*:*:*:*

More vulnerabilities in Apple Mail

CVE-2008-0039 — Medium (CVSS 6.8): Unspecified vulnerability in Mail in Apple Mac OS X 10.4.11 allows remote attackers to execute arbitrary commands via a…
CVE-2017-17689 — Medium (CVSS 5.9): The S/MIME specification allows a Cipher Block Chaining (CBC) malleability-gadget attack that can indirectly lead to…
CVE-2008-4491 — Medium (CVSS 5.0): Apple Mail.app 3.5 on Mac OS X, when "Store draft messages on the server" is enabled, stores draft copies of S/MIME…
CVE-2010-3887 — Medium (CVSS 4.3): The Limit Mail feature in the Parental Controls functionality in Mail on Apple Mac OS X does not properly enforce the…
CVE-2005-2512 — Low (CVSS 2.1): Mail.app in Mac OS 10.4.2 and earlier, when printing or forwarding an HTML message, loads remote images even when the…

All CVEs affecting Apple Mail →