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CVE-2019-17023
After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition…
Medium6.5EPSS 1.3%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition in the TLS State Machine. If the client gets into this state, incoming Application Data records will be ignored. This vulnerability affects Firefox < 72.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 1.3% · top 29% of all CVEs (3 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
- NSS may negotiate TLS 1.2 or below after a TLS 1.3 HelloRetryRequest had been sent
- CWE-287 (opens in a new tab)All about CWE-287 and its CVEs
Affected products
References (5)
- https://bugzilla.mozilla.org/show_bug.cgi?id=1590001 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.mozilla.org/security/advisories/mfsa2020-01/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- USN-4234-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- USN-4397-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- DSA-4726 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-17023)Record last updated .