libcurl versions from 7.36.0 to before 7.64.0 are vulnerable to a stack-based buffer overflow.
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.
- Published
- Feb 6, 2019
- Updated
- Jun 16, 2026
- EPSS
- 12.9% · 96th percentile
- CWE
- CWE-121
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Report tools
Action score
43
Plan
Add it to your regular patch cycle.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 4 / 30 · 12.9%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 9.8
- CNA · redhat
- 7.1
- 2.7 point gap
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| haxx | libcurl | cpe:2.3:a:haxx:libcurl |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| netapp | active iq unified manager | cpe:2.3:a:netapp:active_iq_unified_manager |
| netapp | clustered data ontap | cpe:2.3:a:netapp:clustered_data_ontap |
| netapp | oncommand insight | cpe:2.3:a:netapp:oncommand_insight |
| netapp | oncommand workflow automation | cpe:2.3:a:netapp:oncommand_workflow_automation |
| netapp | snapcenter | cpe:2.3:a:netapp:snapcenter |
| siemens | sinema remote connect client | cpe:2.3:a:siemens:sinema_remote_connect_client |
| oracle | communications operations monitor | cpe:2.3:a:oracle:communications_operations_monitor |
| oracle | enterprise manager ops center | cpe:2.3:a:oracle:enterprise_manager_ops_center |
| oracle | http server | cpe:2.3:a:oracle:http_server |
and 4 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- oracle mysql serverup to 5.7.26 inclusive
- oracle mysql server5.7.27 and later · up to 8.0.15 inclusive
Versions reported by the vendor
Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.
The curl Project curl
- 7.64.0affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.10 | curl | before 7.64.0-r0 | 7.64.0-r0 |
| Alpine:v3.6 | curl | before 7.61.1-r2 | 7.61.1-r2 |
| Debian:12 | curl | before 7.64.0-1 | 7.64.0-1 |
| Debian:8 | curl | before 7.38.0-4+deb8u14 | 7.38.0-4+deb8u14 |
| Debian:9 | curl | before 7.52.1-5+deb9u9 | 7.52.1-5+deb9u9 |
| openSUSE:Leap 15.0 | curl | before 7.60.0-lp150.2.18.1 | 7.60.0-lp150.2.18.1 |
| openSUSE:Leap 15.0 | curl-mini | before 7.60.0-lp150.2.18.1 | 7.60.0-lp150.2.18.1 |
| Red Hat:enterprise_linux:8::baseos | curl | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | curl-debuginfo | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | curl-debugsource | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | curl-minimal-debuginfo | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | libcurl | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | libcurl-debuginfo | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | libcurl-devel | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | libcurl-minimal | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| Red Hat:enterprise_linux:8::baseos | libcurl-minimal-debuginfo | before 0:7.61.1-11.el8 | 0:7.61.1-11.el8 |
| SUSE:Linux Enterprise Desktop 12 SP4 | curl | before 7.60.0-4.3.1 | 7.60.0-4.3.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 | curl | before 7.60.0-3.17.1 | 7.60.0-3.17.1 |
| SUSE:OpenStack Cloud 7 | curl | before 7.37.0-37.34.1 | 7.37.0-37.34.1 |
Same product
haxx: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-38545This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy
handshake.63This week
- CVE-2019-5436A heap buffer overflow in the TFTP receiving code allows for DoS or arbitrary code execution in libcurl versions 7.19.4 through 7.64.1.46Plan
- CVE-2018-14618curl before version 7.61.1 is vulnerable to a buffer overrun in the NTLM authentication code.42Plan
- CVE-2016-8622The URL percent-encoding decode function in libcurl before 7.51.0 is called `curl_easy_unescape`.40Plan
- CVE-2021-22945When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a pointer to an already freed38Monitor
- CVE-2017-1000257An IMAP FETCH response line indicates the size of the returned data, in number of bytes.38Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| alpine:curl | 7.64.0-r0 · Alpine:v3.10 | Package registry (OSV) |
| debian:curl | 7.64.0-1 · Debian:12 | Package registry (OSV) |
| opensuse:curl | 7.60.0-lp150.2.18.1 · openSUSE:Leap 15.0 | Package registry (OSV) |
| opensuse:curl-mini | 7.60.0-lp150.2.18.1 · openSUSE:Leap 15.0 | Package registry (OSV) |
| red hat:curl | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:curl-debuginfo | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:curl-debugsource | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:curl-minimal-debuginfo | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:libcurl | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:libcurl-debuginfo | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:libcurl-devel | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:libcurl-minimal | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| red hat:libcurl-minimal-debuginfo | 0:7.61.1-11.el8 · Red Hat:enterprise_linux:8::baseos | Package registry (OSV) |
| suse:curl | 7.60.0-3.17.1 · SUSE:Linux Enterprise Module for Basesystem 15 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-20-905 · Oct 30, 2020(OpenShift Güvenlik Güncellemesi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-121 · Stack-based Buffer OverflowCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- www.securityfocus.com/bid/106950
- access.redhat.com/errata/RHSA-2019:3701
- cert-portal.siemens.com/productcert/pdf/ssa-436177.pdf
- curl.haxx.se/docs/CVE-2019-3822.html
- lists.apache.org/thread.html/8338a0f605bdbb3a6098bb76f666a95fc2b2f53f37fa1ecc89f1146f%40%3Cdevnull.infra.apache.org%3E
- security.gentoo.org/glsa/201903-03
- security.netapp.com/advisory/ntap-20190315-0001/
- security.netapp.com/advisory/ntap-20190719-0004/
- support.f5.com/csp/article/K84141449
- support.f5.com/csp/article/K84141449?utm_source=f5support&%3Butm_medium=RSS
- usn.ubuntu.com/3882-1/
- www.debian.org/security/2019/dsa-4386
- www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
- www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.