Out-of-bounds write in curl
Priority HIGH 83CWE-787Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-787 and the CVSS impact.
Summary
This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy handshake. When curl is asked to pass along the host name to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that host name can be is 255 bytes. If the host name is detected to be longer, curl switches to local name resolving and instead passes on the resolved address only. Due to this bug, the local variable that means "let the host resolve the name" could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long host name to the target buffer instead of copying just the resolved address there. The target buffer being a heap based buffer, and the host name coming from the URL that curl has been told to operate with.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.78689 99th percentileScored 2026-11-07
Fix Fixed curl (curl): 8.4.0, 7.69.0Red Hat: 7 advisories
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| curl | curl | 8.4.0 to before 8.4.0 | 8.4.0, 7.69.0 | Patch available | CNA |
- curl Vendorcurl Affected 8.4.0 to before 8.4.0 Fixed in 8.4.0, 7.69.0 Patch available CNA
CPE configurations NVD · 14
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:* | 7.69.0 to before 8.4.0 | Vulnerable | Haxx |
| cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:* | 37 | Vulnerable | Fedoraproject |
| cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:windows:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:oncommand_insight:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:* | before 10.0.17763.5122 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:* | before 10.0.19044.3693 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:* | before 10.0.19045.3693 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:* | before 10.0.22000.2600 | Vulnerable | Microsoft |
- cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:* Versions 7.69.0 to before 8.4.0 Vulnerable ·Haxx
- cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:* Versions 37 Vulnerable ·Fedoraproject
- cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:windows:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:oncommand_insight:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:* Versions before 10.0.17763.5122 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:* Versions before 10.0.19044.3693 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:* Versions before 10.0.19045.3693 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:* Versions before 10.0.22000.2600 Vulnerable ·Microsoft
Show 4 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:* | before 10.0.22621.2715 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:* | before 10.0.22631.2715 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* | before 10.0.17763.5122 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* | before 10.0.20348.2113 | Vulnerable | Microsoft |
- cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:* Versions before 10.0.22621.2715 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:* Versions before 10.0.22631.2715 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.5122 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.2113 Vulnerable ·Microsoft
Remediation
- Fix · CNA curl (curl) Fixed in 8.4.0, 7.69.0
Red Hat 7 advisories
- RHSA-2024:2011 Released 2024-04-23 · Red Hat rating ImportantSatellite Client Async Security Update
- Satellite Client 6 for RHEL 6 puppet-agent-7.27.0-1.el6sat
- Satellite Client 6 for RHEL 7 puppet-agent-7.27.0-1.el7sat
- Satellite Client 6 for RHEL 8 puppet-agent-7.27.0-1.el8sat
- Satellite Client 6 for RHEL 9 puppet-agent-7.27.0-1.el9sat
- RHSA-2024:0797 Released 2024-02-13 · Red Hat rating ImportantSatellite 6.14.2 Async Security Update
- Red Hat Satellite 6.14 for RHEL 8 candlepin-4.3.11-1.el8sat, candlepin-selinux-4.3.11-1.el8sat, mosquitto-2.0.17-1.el8sat +5
- RHSA-2023:7626 Released 2023-12-07 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.57 SP2 security update
- Red Hat JBoss Core Services
Show 4 more Red Hat advisories
- RHSA-2023:7625 Released 2023-12-07 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.57 SP2 security update
- Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-curl-8.4.0-2.el7jbcs, jbcs-httpd24-libcurl-8.4.0-2.el7jbcs, jbcs-httpd24-libcurl-devel-8.4.0-2.el7jbcs +8
- Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-curl-8.4.0-2.el8jbcs, jbcs-httpd24-libcurl-8.4.0-2.el8jbcs, jbcs-httpd24-libcurl-devel-8.4.0-2.el8jbcs +8
- RHSA-2023:6745 Released 2023-11-07 · Red Hat rating Importantcurl security update
- Red Hat Enterprise Linux AppStream (v. 9) libcurl-devel-7.76.1-26.el9_3.2
- Red Hat Enterprise Linux BaseOS (v. 9) curl-7.76.1-26.el9_3.2, curl-minimal-7.76.1-26.el9_3.2, libcurl-7.76.1-26.el9_3.2 +1
- RHSA-2023:5763 Released 2023-10-17 · Red Hat rating Importantcurl security update
- Red Hat Enterprise Linux AppStream (v. 9) libcurl-devel-7.76.1-23.el9_2.4
- Red Hat Enterprise Linux BaseOS (v. 9) curl-7.76.1-23.el9_2.4, curl-minimal-7.76.1-23.el9_2.4, libcurl-7.76.1-23.el9_2.4 +1
- RHSA-2023:5700 Released 2023-10-13 · Red Hat rating Importantcurl security update
- Red Hat Enterprise Linux AppStream EUS (v.9.0) libcurl-devel-7.76.1-14.el9_0.9
- Red Hat Enterprise Linux BaseOS EUS (v.9.0) curl-7.76.1-14.el9_0.9, curl-minimal-7.76.1-14.el9_0.9, libcurl-7.76.1-14.el9_0.9 +1
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2023:5763, RHSA-2023:6745 |
| Red Hat Enterprise Linux AppStream EUS (v.9.0) | Fixed | RHSA-2023:5700 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2023:5763, RHSA-2023:6745 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.0) | Fixed | RHSA-2023:5700 |
| Red Hat JBoss Core Services | Fixed | RHSA-2023:7626 |
| Red Hat JBoss Core Services on RHEL 7 Server | Fixed | RHSA-2023:7625 |
| Red Hat JBoss Core Services on RHEL 8 | Fixed | RHSA-2023:7625 |
| Red Hat Satellite 6.14 for RHEL 8 | Fixed | RHSA-2024:0797 |
| Satellite Client 6 for RHEL 6 | Fixed | RHSA-2024:2011 |
| Satellite Client 6 for RHEL 7 | Fixed | RHSA-2024:2011 |
| Satellite Client 6 for RHEL 8 | Fixed | RHSA-2024:2011 |
| Satellite Client 6 for RHEL 9 | Fixed | RHSA-2024:2011 |
Not affected: 10 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat JBoss Core Services on RHEL 7 Server
- Red Hat JBoss Core Services on RHEL 8
- Red Hat Satellite 6.14 for RHEL 8
- Satellite Client 6 for RHEL 6
- Satellite Client 6 for RHEL 7
- Satellite Client 6 for RHEL 8
- Satellite Client 6 for RHEL 9
Timeline
- 2026-10-02 Threatist record created from CVE-2023-38545
- 2026-10-03 Alias added: GHSA-7xw9-w465-6x42
- 2026-10-09 Fix available: RHSA-2023:7626 · Red Hat
- 2026-10-16 Fix available: Red Hat JBoss Core Services · Red Hat
References
Patch 2
Advisory 10
- https://security.netapp.com/advisory/ntap-20231027-0009/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/OGMXNRNSJ4ETDK6FRNU3J7SABXPWCHSQ/
- https://support.apple.com/kb/HT214036
- https://support.apple.com/kb/HT214063
- https://support.apple.com/kb/HT214057
- https://support.apple.com/kb/HT214058
- http://seclists.org/fulldisclosure/2024/Jan/34
- http://seclists.org/fulldisclosure/2024/Jan/37
- http://seclists.org/fulldisclosure/2024/Jan/38
- https://security.netapp.com/advisory/ntap-20240201-0005/
More curl vulnerabilities
- TI-2026-16162 Negotiate ambient user conn reuse CVSS 3.1CRITICAL 9.8
- TI-2026-10231 cross-origin Digest auth state leak CVSS 3.1CRITICAL 9.8
- TI-2026-09063 HTTP/2 stream-dependency tree UAF CVSS 3.1CRITICAL 9.8
- TI-2026-07976 stale proxy password leak CVSS 3.1CRITICAL 9.8
- TI-2026-07845 SASL double-free CVSS 3.1CRITICAL 9.8
- TI-2026-77670 Credential leak in curl redirects to URLs with userinfo CVSS 3.1CRITICAL 9.1
Sources
- CVE-2023-38545 · CVE Program
- CVE-2023-38545 · NVD
- FIRST EPSS
- GHSA-7xw9-w465-6x42 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-38545 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences