No exploitation reportedFix available

CVE-2019-11840

Q: Is CVE-2019-11840 actively exploited?

Active exploitation of CVE-2019-11840 has not been confirmed. Its EPSS score was 3.5% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2019-11840?

CVE-2019-11840 has a CVSS v3 base score of 5.9 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

No exploitation reported by the sources we read.

Published2019-05-09
WeaknessCWE-330

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

An issue was discovered in the supplementary Go cryptography library, golang.org/x/crypto, before v0.0.0-20190320223903-b7391e95e576. A flaw was found in the amd64 implementation of the golang.org/x/crypto/salsa20 and golang.org/x/crypto/salsa20/salsa packages. If more than 256 GiB of keystream is generated, or if the counter otherwise grows greater than 32 bits, the amd64 implementation will first generate incorrect output, and then cycle back to previously generated keystream. Repeated keystream bytes can lead to loss of confidentiality in encryption applications, or to predictability in CSPRNG applications.

Timeline

dates in UTC

2019-05-0916:29CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2019-11840?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2019-11840?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Debian debian linux

Branch	Affected	Fixed in	Source
8.0	= 8.0	no fix published	NVD
9.0	= 9.0	no fix published	NVD
10.0	= 10.0	no fix published	NVD

Golang crypto

Branch	Affected	Fixed in	Source
—	all versions	no fix published	NVD

golang.org/x/crypto

Branch	Affected	Fixed in	Source
0.0	< 0.0.0-20190320223903-b7391e95e576	0.0.0-20190320223903-b7391e95e576	OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

bugzilla.redhat.comVendor Advisory
go.googlesource.comPatch

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.15.9read 2026-10-23
NVDCVSS 2.04.3read 2026-10-23
NVDweakness (CWE)CWE-330read 2026-10-23
FIRST EPSSEPSS score3.5 %2026-10-22
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Published: 2019-05-09
Last Modified: 2026-06-17
NVD status: Analyzed

Frequently asked questions

What is CVE-2019-11840?

Is CVE-2019-11840 actively exploited?

Active exploitation of CVE-2019-11840 has not been confirmed. Its EPSS score was 3.5% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-11840?

CVE-2019-11840 has a CVSS v3 base score of 5.9 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

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