The Twitter Kit framework through 3.4.2 for iOS does not properly validate the api.twitter.com SSL certificate.

published 2019-10-07 7y ago modified 2026-06-17 4mo ago also EUVD-2019-7066

cvss: 7.4; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

The Twitter Kit framework through 3.4.2 for iOS does not properly validate the api.twitter.com SSL certificate. Although the certificate chain must contain one of a set of pinned certificates, there are certain implementation errors such as a lack of hostname verification. NOTE: this is an end-of-life product.

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Exploit prediction

1.03% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

sit.fraunhofer.de https://www.sit.fraunhofer.de/fileadmin/dokumente/CVE/Advisory_TwitterKit_for_iOS_CVE-2019-16263.pdf referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.4	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD	2.0	5.8	AV:N/AC:M/Au:N/C:P/I:P/A:N

Classification

Weakness

CWE-295 Improper Certificate Validation

References

sit.fraunhofer.de /fileadmin/dokumente/CVE/Advisory_TwitterKit_for_iOS_CVE-2019-16263.pdf
exploit, third-party-advisory
github.com /twitter-archive/twitter-kit-ios/blob/ac42e1351a66afa5ff7718d04d64a905dafe1f41/TwitterCore/TwitterCore/Network
third-party-advisory
blog.appicaptor.com /2019/10/04/vulnerable-library-warning-twitterkit-for-ios/
third-party-advisory

Sources

CVE List CVE-2019-16263
NVD CVE-2019-16263

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