curl: NTLMv2 type-3 header stack buffer overflow
Published Feb 6, 2019
9.8
CRITICALCVSS 3.1
EPSS 12.87%
Description
libcurl versions from 7.36.0 to before 7.64.0 are vulnerable to a stack-based buffer overflow. The function creating an outgoing NTLM type-3 header (`lib/vauth/ntlm.c:Curl_auth_create_ntlm_type3_message()`), generates the request HTTP header contents based on previously received data. The check that exists to prevent the local buffer from getting overflowed is implemented wrongly (using unsigned math) and as such it does not prevent the overflow from happening. This output data can grow larger than the local buffer if very large 'nt response' data is extracted from a previous NTLMv2 header provided by the malicious or broken HTTP server. Such a 'large value' needs to be around 1000 bytes or more. The actual payload data copied to the target buffer comes from the NTLMv2 type-2 response header.
Affected products
-
- Version 7.64.0StatusaffectedConstraints-
- 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 |
|
Configuration 2
- 14.04
- 16.04
- 18.04
- 18.10
Configuration 3
- 9.0
Configuration 4
- ≥ 7.3
- ≥ 9.5
- n/a
- n/a
- n/a
- n/a
Configuration 5
- ≤ 2.0
Configuration 6
- 3.4
- 4.0
- 12.3.3
- 12.4.0
- 12.2.1.3.0
- ≤ 5.7.26
- ≥ 5.7.27 · ≤ 8.0.15
- 5.4
- 19.2
Configuration 7
- 8.0
No data.
JBoss Core Services Apache HTTP Server 2.4.29 SP2
n/a
Fixed · RHSA-2019:1543
Red Hat Enterprise Linux 8
curl-0:7.61.1-11.el8
Fixed · RHSA-2019:3701
.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 2.1 on Red Hat Enterprise Linux
rh-dotnet21-curl
Will not fix
.NET Core 2.2 on Red Hat Enterprise Linux
rh-dotnet22-curl
Out of support scope
Red Hat Enterprise Linux 5
curl
Not affected
Red Hat Enterprise Linux 6
curl
Not affected
Red Hat Enterprise Linux 7
curl
Not affected
Red Hat JBoss Core Services
jbcs-httpd24-curl
Affected
Red Hat JBoss Web Server 5
curl
Not affected
Red Hat Software Collections
httpd24-curl
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| JBoss Core Services Apache HTTP Server 2.4.29 SP2 | n/a | Fixed | RHSA-2019:1543 |
| Red Hat Enterprise Linux 8 | curl-0:7.61.1-11.el8 | Fixed | RHSA-2019:3701 |
| .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 2.1 on Red Hat Enterprise Linux | rh-dotnet21-curl | Will not fix | n/a |
| .NET Core 2.2 on Red Hat Enterprise Linux | rh-dotnet22-curl | Out of support scope | n/a |
| Red Hat Enterprise Linux 5 | curl | Not affected | n/a |
| Red Hat Enterprise Linux 6 | curl | Not affected | n/a |
| Red Hat Enterprise Linux 7 | curl | Not affected | n/a |
| Red Hat JBoss Core Services | jbcs-httpd24-curl | Affected | n/a |
| Red Hat JBoss Web Server 5 | curl | Not affected | n/a |
| Red Hat Software Collections | httpd24-curl | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
The versions of curl package shipped with Red Hat Enterprise Linux 5, 6, and 7 do not support NTLMv2 type-3 headers, hence they are not affected by this flaw.
Red Hat mitigation
Turn off NTLM authentication.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
AV:N/AC:L/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Apr 15, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (36 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 12.87% (0.12873) | 96.19th | v5 (v2026.06.15) |
| Jun 15, 2026 | 12.77% (0.12771) | 95.76th | v5 (v2026.06.15) |
| May 3, 2026 | 17.89% (0.17889) | 95.17th | v4 (v2025.03.14) |
| Mar 16, 2026 | 16.57% (0.16566) | 94.82th | v4 (v2025.03.14) |
| Dec 28, 2025 | 27.87% (0.27871) | 96.29th | v4 (v2025.03.14) |
| Dec 27, 2025 | 25.93% (0.25931) | 96.12th | v4 (v2025.03.14) |
| Nov 22, 2025 | 27.87% (0.27871) | 96.26th | v4 (v2025.03.14) |
| Nov 21, 2025 | 31.95% (0.31945) | 96.62th | v4 (v2025.03.14) |
| Nov 18, 2025 | 35.62% (0.35620) | 96.86th | v4 (v2025.03.14) |
| Nov 10, 2025 | 31.95% (0.31945) | 96.60th | v4 (v2025.03.14) |
| Oct 28, 2025 | 26.44% (0.26443) | 96.08th | v4 (v2025.03.14) |
| Oct 27, 2025 | 24.56% (0.24561) | 95.88th | v4 (v2025.03.14) |
| Oct 1, 2025 | 26.44% (0.26443) | 96.17th | v4 (v2025.03.14) |
| Aug 30, 2025 | 24.56% (0.24561) | 95.91th | v4 (v2025.03.14) |
| Jul 30, 2025 | 30.92% (0.30924) | 96.55th | v4 (v2025.03.14) |
| Jun 19, 2025 | 33.93% (0.33935) | 96.74th | v4 (v2025.03.14) |
| May 18, 2025 | 36.85% (0.36847) | 96.92th | v4 (v2025.03.14) |
| Mar 30, 2025 | 33.93% (0.33935) | 96.60th | v4 (v2025.03.14) |
| Mar 29, 2025 | 58.68% (0.58683) | 97.43th | v4 (v2025.03.14) |
| Mar 19, 2025 | 33.93% (0.33935) | 96.44th | v4 (v2025.03.14) |
| Mar 17, 2025 | 19.68% (0.19678) | 94.96th | v4 (v2025.03.14) |
| Dec 17, 2024 | 7.85% (0.07855) | 94.21th | v3 (v2023.03.01) |
| Aug 8, 2024 | 19.21% (0.19215) | 96.34th | v3 (v2023.03.01) |
| Jun 29, 2024 | 14.97% (0.14971) | 95.85th | v3 (v2023.03.01) |
| Jan 31, 2024 | 17.09% (0.17091) | 95.61th | v3 (v2023.03.01) |
| Nov 8, 2023 | 22.34% (0.22342) | 95.99th | v3 (v2023.03.01) |
| Aug 5, 2023 | 35.52% (0.35521) | 96.58th | v3 (v2023.03.01) |
| Jun 2, 2023 | 36.62% (0.36624) | 96.59th | v3 (v2023.03.01) |
| Mar 7, 2023 | 31.74% (0.31742) | 96.27th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.69% (0.02686) | 82.85th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.69% (0.02686) | 81.17th | v2 (v2022.01.01) |
| Feb 4, 2022 | 24.56% (0.24563) | 95.26th | v2 (v2022.01.01) |
| Feb 3, 2022 | 13.21% (0.13208) | 89.07th | v5 (v2026.06.15) |
| Jan 6, 2022 | 13.21% (0.13208) | 88.94th | v1 |
| Sep 1, 2021 | 3.28% (0.03281) | 81.60th | v1 |
| Apr 14, 2021 | 3.28% (0.03281) | 0.00th | v1 |
References (19)
- http://www.securityfocus.com/bid/106950 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2019:3701 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2019-3822 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1670254 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3822 x_refsource_CONFIRMExploitIssue TrackingPatchThird Party Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-436177.pdf x_refsource_CONFIRMThird Party Advisory
- https://curl.haxx.se/docs/CVE-2019-3822.html x_refsource_MISCPatchVendor Advisory
- https://lists.apache.org/thread.html/8338a0f605bdbb3a6098bb76f666a95fc2b2f53f37fa1ecc89f1146f%40%3Cdevnull.infra.apache.org%3E mailing-listx_refsource_MLIST
- https://nvd.nist.gov/vuln/detail/CVE-2019-3822
- https://security.gentoo.org/glsa/201903-03 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://security.netapp.com/advisory/ntap-20190315-0001/ x_refsource_CONFIRMPatchThird Party Advisory
- https://security.netapp.com/advisory/ntap-20190719-0004/ x_refsource_CONFIRMThird Party Advisory
- https://support.f5.com/csp/article/K84141449 x_refsource_CONFIRMThird Party Advisory
- https://support.f5.com/csp/article/K84141449?utm_source=f5support&%3Butm_medium=RSS x_refsource_CONFIRM
- https://usn.ubuntu.com/3882-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2019-3822
- https://www.debian.org/security/2019/dsa-4386 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html x_refsource_MISCPatchThird Party Advisory
- https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html x_refsource_MISCPatchThird Party Advisory
Change history (6)
- MITRE
- CVSS severity changed from MEDIUM to
HIGH MEDIUM → HIGH
- CVSS vector changed from CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H to
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H → CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
- CVSS score changed from 5.3 to
7.1 5.3 → 7.1
- CVSS severity changed from MEDIUM to
HIGH
- REDHAT
- CVSS severity changed from HIGH to
MEDIUM HIGH → MEDIUM
- CVSS vector changed from CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H to
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H → CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
- CVSS score changed from 7.1 to
5.3 7.1 → 5.3
- CVSS severity changed from HIGH to
MEDIUM