How severe is CVE-2019-11340?

CVE-2019-11340 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 none, integrity high, and availability none.

Is CVE-2019-11340 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-11340?

CVE-2019-11340 affects Matrix Sydent. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-11340?

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

When was CVE-2019-11340 published?

CVE-2019-11340 was published on 2019-04-19 and last updated on 2026-06-17.

CVE-2019-11340

CVE-2019-11340 is a medium-severity vulnerability in Matrix Sydent 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. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Matrix Sydent
Published: 2019-04-19
Last modified: 2026-06-17

Description

util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on [email protected]@good.example.com returns the [email protected] substring.

Frequently asked questions

What is CVE-2019-11340?: util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on [email protected]@good.example.com returns the [email protected] substring.
How severe is CVE-2019-11340?: CVE-2019-11340 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 none, integrity high, and availability none.
Is CVE-2019-11340 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-11340?: CVE-2019-11340 affects Matrix Sydent. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-11340?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-11340 published?: CVE-2019-11340 was published on 2019-04-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:matrix:sydent:*:*:*:*:*:*:*:*

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