CVE-2016-3959

mediumpriority · track · 42EPSS 0.044 · 91 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

4.36% (91st) EPSS

CVSS 5 · medium

Is it mine?

16 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

The Verify function in crypto/dsa/dsa.go in Go before 1.5.4 and 1.6.x before 1.6.1 does not properly check parameters passed to the big integer library, which might allow remote attackers to cause a denial of service (infinite loop) via a crafted public key to a program that uses HTTPS client certificates or SSH server libraries.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedgolang-0:1.6.3-1.el7_2.1.src as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-0:1.6.3-1.el7_2.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-bin-0:1.6.3-1.el7_2.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-docs-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-misc-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-src-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538
Fixedgolang-tests-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2016:1538

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Psecondary · Red Hat Product Security US

v3.07.1highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Psecondary · CVSS-BT (t0sche)

v3.05.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · Red Hat Product Security US

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-835US

exploits (1)

Public proof-of-concept and weaponised exploit code.

alexmullins/dsaAnalysis of CVE-2016-3959 and a Proof of Concept Attack Against a Go SSH Server. PoC · poc_in_github

affected products (16)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
fedoraproject fedora= 22nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 23nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 24nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
golang go≤ 1.5nvdUScpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
golang go= 1.6nvdUScpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
opensuse leap= 42.1nvdUScpe:2.3:o:opensuse:leap:*:*:*:*:*:*:*:*
Go stdlib< 1.5.4osvUSpkg:golang/stdlib
Go stdlib1.6.0-0 → 1.6.1osvUSpkg:golang/stdlib
golang-0:1.6.3-1.el7_2.1.src as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-0:1.6.3-1.el7_2.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-bin-0:1.6.3-1.el7_2.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-docs-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-misc-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-src-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS
golang-tests-0:1.6.3-1.el7_2.1.noarch as a component of Red Hat Enterprise Linux Server Optional (v. 7)all versionsfixedredhat_csafUS

advisories (2)

Vendor and ecosystem advisories describing this.

RHSA-2016:1538Red Hat Security Advisory: golang security, bug fix, and enhancement update2016-08-02csaf · redhat_csafUS
An update for golang is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
GO-2022-0166Denial of service due to unchecked parameters in crypto/dsa2022-05-24vendor · osvUS
The Verify function in crypto/dsa passed certain parameters unchecked to the underlying big integer library, possibly leading to extremely long-running computations, which in turn makes Go programs vulnerable to remote denial of service attacks. Programs using HTTPS client certificates or the Go SSH server libraries are both exposed to this vulnerability.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv redhat_csaf NVD CVE.org MITRE

published 2016-05-23modified 2026-06-17

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references (27)

External citations — patches, advisories, analysis.

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