CVE-2017-17843

An issue was discovered in Enigmail before 1.9.9 that allows remote attackers to trigger use of an intended public key for encryption, because incorrect regular expressions are used for extraction of an e-mail address from a comma-separated list, as demonstrated by a modified Full Name field and a homograph attack, aka TBE-01-002.

Published: 2017-12-27 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2017-17843 is rated Low Risk (37.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.20%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-17843

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.43% 0.20% -0.22%
2 2025-03-29 0.20% 0.43% +0.22%
3 2025-03-17 0.20%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-17843

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
8.6 2.9 [email protected]

Weakness enumeration for CVE-2017-17843

OS Trackers for CVE-2017-17843

vendor priority summary link
debian not yet assigned CVE-2017-17843 not yet assigned priority: Debian including 1 source packages (enigmail), 1 status rows across 1 suites (bullseye): resolved 1. https://security-tracker.debian.org/tracker/CVE-2017-17843
ubuntu high CVE-2017-17843 high priority: Ubuntu including 1 source packages (enigmail), 5 status rows across 5 suites (artful, trusty, upstream, xenial, zesty): released 4, ignored 1. https://ubuntu.com/security/CVE-2017-17843

Affected software / configurations for CVE-2017-17843

Vendor Product Version Raw CPE
enigmail enigmail < 1.9.9 cpe:2.3:a:enigmail:enigmail:*:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

References for CVE-2017-17843

cvelogic Threat Intelligence