curl: Case insensitive password comparison
Published Aug 1, 2018
5.9
MEDIUMCVSS 3.0
EPSS 3.47%
Description
A flaw was found in curl before version 7.51.0 When re-using a connection, curl was doing case insensitive comparisons of user name and password with the existing connections. This means that if an unused connection with proper credentials exists for a protocol that has connection-scoped credentials, an attacker can cause that connection to be reused if s/he knows the case-insensitive version of the correct password.
Affected products
-
- Version 7.51.0StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| The Curl Project | Curl | n/a |
|
No data.
Red Hat JBoss Core Services
jbcs-httpd24-curl
Fixed · RHSA-2018:2486
Red Hat Software Collections for Red Hat Enterprise Linux 6
httpd24-curl-0:7.61.1-1.el6
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 6
httpd24-httpd-0:2.4.34-7.el6
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 6
httpd24-nghttp2-0:1.7.1-7.el6
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7
httpd24-curl-0:7.61.1-1.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7
httpd24-httpd-0:2.4.34-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7
httpd24-nghttp2-0:1.7.1-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS
httpd24-curl-0:7.61.1-1.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS
httpd24-httpd-0:2.4.34-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS
httpd24-nghttp2-0:1.7.1-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS
httpd24-curl-0:7.61.1-1.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS
httpd24-httpd-0:2.4.34-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS
httpd24-nghttp2-0:1.7.1-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS
httpd24-curl-0:7.61.1-1.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS
httpd24-httpd-0:2.4.34-7.el7
Fixed · RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS
httpd24-nghttp2-0:1.7.1-7.el7
Fixed · RHSA-2018:3558
.NET Core 1.0 on Red Hat Enterprise Linux
rh-dotnetcore10-curl
Out of support scope
.NET Core 1.1 on Red Hat Enterprise Linux
rh-dotnetcore11-curl
Out of support scope
.NET Core 2.0 on Red Hat Enterprise Linux
rh-dotnet20-curl
Out of support scope
Red Hat Enterprise Linux 5
curl
Will not fix
Red Hat Enterprise Linux 6
curl
Will not fix
Red Hat Enterprise Linux 7
curl
Will not fix
Red Hat Enterprise Virtualization 3
mingw-virt-viewer
Will not fix
Red Hat JBoss Enterprise Web Server 3
curl
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat JBoss Core Services | jbcs-httpd24-curl | Fixed | RHSA-2018:2486 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | httpd24-curl-0:7.61.1-1.el6 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | httpd24-httpd-0:2.4.34-7.el6 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | httpd24-nghttp2-0:1.7.1-7.el6 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | httpd24-curl-0:7.61.1-1.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | httpd24-httpd-0:2.4.34-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | httpd24-nghttp2-0:1.7.1-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS | httpd24-curl-0:7.61.1-1.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS | httpd24-httpd-0:2.4.34-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS | httpd24-nghttp2-0:1.7.1-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | httpd24-curl-0:7.61.1-1.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | httpd24-httpd-0:2.4.34-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | httpd24-nghttp2-0:1.7.1-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | httpd24-curl-0:7.61.1-1.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | httpd24-httpd-0:2.4.34-7.el7 | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | httpd24-nghttp2-0:1.7.1-7.el7 | Fixed | RHSA-2018:3558 |
| .NET Core 1.0 on Red Hat Enterprise Linux | rh-dotnetcore10-curl | Out of support scope | n/a |
| .NET Core 1.1 on Red Hat Enterprise Linux | rh-dotnetcore11-curl | Out of support scope | n/a |
| .NET Core 2.0 on Red Hat Enterprise Linux | rh-dotnet20-curl | Out of support scope | n/a |
| Red Hat Enterprise Linux 5 | curl | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | curl | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | curl | Will not fix | n/a |
| Red Hat Enterprise Virtualization 3 | mingw-virt-viewer | Will not fix | n/a |
| Red Hat JBoss Enterprise Web Server 3 | curl | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
AV:N/AC:M/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (19 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 3.47% (0.03472) | 88.69th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.50% (0.03501) | 87.62th | v5 (v2026.06.15) |
| Mar 15, 2026 | 4.13% (0.04130) | 88.48th | v4 (v2025.03.14) |
| Nov 30, 2025 | 2.94% (0.02940) | 85.98th | v4 (v2025.03.14) |
| Oct 15, 2025 | 4.75% (0.04747) | 88.90th | v4 (v2025.03.14) |
| Aug 24, 2025 | 2.68% (0.02677) | 85.24th | v4 (v2025.03.14) |
| Mar 30, 2025 | 4.09% (0.04092) | 87.51th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.24% (0.02241) | 74.20th | v4 (v2025.03.14) |
| Mar 17, 2025 | 4.90% (0.04904) | 88.87th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.57% (0.00570) | 78.59th | v3 (v2023.03.01) |
| Apr 11, 2024 | 0.56% (0.00562) | 77.38th | v3 (v2023.03.01) |
| Feb 1, 2024 | 0.56% (0.00562) | 75.37th | v3 (v2023.03.01) |
| Dec 23, 2023 | 0.52% (0.00523) | 74.35th | v3 (v2023.03.01) |
| Jul 26, 2023 | 0.56% (0.00557) | 74.61th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.49% (0.00493) | 72.46th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.54% (0.01537) | 74.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
References (14)
- http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html x_refsource_CONFIRMPatch
- http://www.securityfocus.com/bid/94094 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1037192 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2018:2486 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3558 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2016-8616 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1388371 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-8616 x_refsource_CONFIRMIssue TrackingPatchVendor Advisory
- https://curl.haxx.se/CVE-2016-8616.patch x_refsource_CONFIRMPatchVendor Advisory
- https://curl.haxx.se/docs/adv_20161102B.html x_refsource_CONFIRMPatchVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2016-8616
- https://security.gentoo.org/glsa/201701-47 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2016-8616
- https://www.tenable.com/security/tns-2016-21 x_refsource_CONFIRMThird Party Advisory
Change history (0)
No recorded changes yet.