Credentials leaked to HTTP proxy in curl
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Partial Red Hat: 1 fixed, 8 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-201.
Summary
Affected are curl releases including 8.22.0, 8.21.0 and 8.20.0, back to 7.10.8. An HTTP proxy can make libcurl send the origin's credentials to the proxy itself (CWE-201). A proxy that answers a CONNECT request with 401 WWW-Authenticate instead of 407 Proxy-Authenticate triggers this, and a remote attacker needs no privileges or user interaction. CISA SSVC rates exploitation as proof of concept.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
Description from the CNA
An HTTP proxy can trick libcurl into sending the origin's credentials (Basic password, or a Negotiate/Kerberos ticket) to the proxy itself, by answering the `CONNECT` tunnel request with 401 `WWW-Authenticate:` instead of the expected 407 `Proxy-Authenticate:`.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- 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 | 8.22.0 – 8.22.0; 8.21.0 – 8.21.0; 8.20.0 – 8.20.0; 8.19.0 – 8.19.0; 8.18.0 – 8.18.0; 8.17.0 – 8.17.0; 8.16.0 – 8.16.0; 8.15.0 – 8.15.0; 8.14.1 – 8.14.1; 8.14.0 – 8.14.0; 8.13.0 – 8.13.0; 8.12.1 – 8.12.1; 8.12.0 – 8.12.0; 8.11.1 – 8.11.1; 8.11.0 – 8.11.0; 8.10.1 – 8.10.1; 8.10.0 – 8.10.0; 8.9.1 – 8.9.1; 8.9.0 – 8.9.0; 8.8.0 – 8.8.0; 8.7.1 – 8.7.1; 8.7.0 – 8.7.0; 8.6.0 – 8.6.0; 8.5.0 – 8.5.0; 8.4.0 – 8.4.0; 8.3.0 – 8.3.0; 8.2.1 – 8.2.1; 8.2.0 – 8.2.0; 8.1.2 – 8.1.2; 8.1.1 – 8.1.1; 8.1.0 – 8.1.0; 8.0.1 – 8.0.1; 8.0.0 – 8.0.0; 7.88.1 – 7.88.1; 7.88.0 – 7.88.0; 7.87.0 – 7.87.0; 7.86.0 – 7.86.0; 7.85.0 – 7.85.0; 7.84.0 – 7.84.0; 7.83.1 – 7.83.1; 7.83.0 – 7.83.0; 7.82.0 – 7.82.0; 7.81.0 – 7.81.0; 7.80.0 – 7.80.0; 7.79.1 – 7.79.1; 7.79.0 – 7.79.0; 7.78.0 – 7.78.0; 7.77.0 – 7.77.0; 7.76.1 – 7.76.1; 7.76.0 – 7.76.0; 7.75.0 – 7.75.0; 7.74.0 – 7.74.0; 7.73.0 – 7.73.0; 7.72.0 – 7.72.0; 7.71.1 – 7.71.1; 7.71.0 – 7.71.0; 7.70.0 – 7.70.0; 7.69.1 – 7.69.1; 7.69.0 – 7.69.0; 7.68.0 – 7.68.0; 7.67.0 – 7.67.0; 7.66.0 – 7.66.0; 7.65.3 – 7.65.3; 7.65.2 – 7.65.2; 7.65.1 – 7.65.1; 7.65.0 – 7.65.0; 7.64.1 – 7.64.1; 7.64.0 – 7.64.0; 7.63.0 – 7.63.0; 7.62.0 – 7.62.0; 7.61.1 – 7.61.1; 7.61.0 – 7.61.0; 7.60.0 – 7.60.0; 7.59.0 – 7.59.0; 7.58.0 – 7.58.0; 7.57.0 – 7.57.0; 7.56.1 – 7.56.1; 7.56.0 – 7.56.0; 7.55.1 – 7.55.1; 7.55.0 – 7.55.0; 7.54.1 – 7.54.1; 7.54.0 – 7.54.0; 7.53.1 – 7.53.1; 7.53.0 – 7.53.0; 7.52.1 – 7.52.1; 7.52.0 – 7.52.0; 7.51.0 – 7.51.0; 7.50.3 – 7.50.3; 7.50.2 – 7.50.2; 7.50.1 – 7.50.1; 7.50.0 – 7.50.0; 7.49.1 – 7.49.1; 7.49.0 – 7.49.0; 7.48.0 – 7.48.0; 7.47.1 – 7.47.1; 7.47.0 – 7.47.0; 7.46.0 – 7.46.0; 7.45.0 – 7.45.0; 7.44.0 – 7.44.0; 7.43.0 – 7.43.0; 7.42.1 – 7.42.1; 7.42.0 – 7.42.0; 7.41.0 – 7.41.0; 7.40.0 – 7.40.0; 7.39.0 – 7.39.0; 7.38.0 – 7.38.0; 7.37.1 – 7.37.1; 7.37.0 – 7.37.0; 7.36.0 – 7.36.0; 7.35.0 – 7.35.0; 7.34.0 – 7.34.0; 7.33.0 – 7.33.0; 7.32.0 – 7.32.0; 7.31.0 – 7.31.0; 7.30.0 – 7.30.0; 7.29.0 – 7.29.0; 7.28.1 – 7.28.1; 7.28.0 – 7.28.0; 7.27.0 – 7.27.0; 7.26.0 – 7.26.0; 7.25.0 – 7.25.0; 7.24.0 – 7.24.0; 7.23.1 – 7.23.1; 7.23.0 – 7.23.0; 7.22.0 – 7.22.0; 7.21.7 – 7.21.7; 7.21.6 – 7.21.6; 7.21.5 – 7.21.5; 7.21.4 – 7.21.4; 7.21.3 – 7.21.3; 7.21.2 – 7.21.2; 7.21.1 – 7.21.1; 7.21.0 – 7.21.0; 7.20.1 – 7.20.1; 7.20.0 – 7.20.0; 7.19.7 – 7.19.7; 7.19.6 – 7.19.6; 7.19.5 – 7.19.5; 7.19.4 – 7.19.4; 7.19.3 – 7.19.3; 7.19.2 – 7.19.2; 7.19.1 – 7.19.1; 7.19.0 – 7.19.0; 7.18.2 – 7.18.2; 7.18.1 – 7.18.1; 7.18.0 – 7.18.0; 7.17.1 – 7.17.1; 7.17.0 – 7.17.0; 7.16.4 – 7.16.4; 7.16.3 – 7.16.3; 7.16.2 – 7.16.2; 7.16.1 – 7.16.1; 7.16.0 – 7.16.0; 7.15.5 – 7.15.5; 7.15.4 – 7.15.4; 7.15.3 – 7.15.3; 7.15.2 – 7.15.2; 7.15.1 – 7.15.1; 7.15.0 – 7.15.0; 7.14.1 – 7.14.1; 7.14.0 – 7.14.0; 7.13.2 – 7.13.2; 7.13.1 – 7.13.1; 7.13.0 – 7.13.0; 7.12.3 – 7.12.3; 7.12.2 – 7.12.2; 7.12.1 – 7.12.1; 7.12.0 – 7.12.0; 7.11.2 – 7.11.2; 7.11.1 – 7.11.1; 7.11.0 – 7.11.0; 7.10.8 – 7.10.8 | — | No fix listed | CNA |
- curl Vendorcurl Affected 8.22.0 – 8.22.0; 8.21.0 – 8.21.0; 8.20.0 – 8.20.0; 8.19.0 – 8.19.0; 8.18.0 – 8.18.0; 8.17.0 – 8.17.0; 8.16.0 – 8.16.0; 8.15.0 – 8.15.0; 8.14.1 – 8.14.1; 8.14.0 – 8.14.0; 8.13.0 – 8.13.0; 8.12.1 – 8.12.1; 8.12.0 – 8.12.0; 8.11.1 – 8.11.1; 8.11.0 – 8.11.0; 8.10.1 – 8.10.1; 8.10.0 – 8.10.0; 8.9.1 – 8.9.1; 8.9.0 – 8.9.0; 8.8.0 – 8.8.0; 8.7.1 – 8.7.1; 8.7.0 – 8.7.0; 8.6.0 – 8.6.0; 8.5.0 – 8.5.0; 8.4.0 – 8.4.0; 8.3.0 – 8.3.0; 8.2.1 – 8.2.1; 8.2.0 – 8.2.0; 8.1.2 – 8.1.2; 8.1.1 – 8.1.1; 8.1.0 – 8.1.0; 8.0.1 – 8.0.1; 8.0.0 – 8.0.0; 7.88.1 – 7.88.1; 7.88.0 – 7.88.0; 7.87.0 – 7.87.0; 7.86.0 – 7.86.0; 7.85.0 – 7.85.0; 7.84.0 – 7.84.0; 7.83.1 – 7.83.1; 7.83.0 – 7.83.0; 7.82.0 – 7.82.0; 7.81.0 – 7.81.0; 7.80.0 – 7.80.0; 7.79.1 – 7.79.1; 7.79.0 – 7.79.0; 7.78.0 – 7.78.0; 7.77.0 – 7.77.0; 7.76.1 – 7.76.1; 7.76.0 – 7.76.0; 7.75.0 – 7.75.0; 7.74.0 – 7.74.0; 7.73.0 – 7.73.0; 7.72.0 – 7.72.0; 7.71.1 – 7.71.1; 7.71.0 – 7.71.0; 7.70.0 – 7.70.0; 7.69.1 – 7.69.1; 7.69.0 – 7.69.0; 7.68.0 – 7.68.0; 7.67.0 – 7.67.0; 7.66.0 – 7.66.0; 7.65.3 – 7.65.3; 7.65.2 – 7.65.2; 7.65.1 – 7.65.1; 7.65.0 – 7.65.0; 7.64.1 – 7.64.1; 7.64.0 – 7.64.0; 7.63.0 – 7.63.0; 7.62.0 – 7.62.0; 7.61.1 – 7.61.1; 7.61.0 – 7.61.0; 7.60.0 – 7.60.0; 7.59.0 – 7.59.0; 7.58.0 – 7.58.0; 7.57.0 – 7.57.0; 7.56.1 – 7.56.1; 7.56.0 – 7.56.0; 7.55.1 – 7.55.1; 7.55.0 – 7.55.0; 7.54.1 – 7.54.1; 7.54.0 – 7.54.0; 7.53.1 – 7.53.1; 7.53.0 – 7.53.0; 7.52.1 – 7.52.1; 7.52.0 – 7.52.0; 7.51.0 – 7.51.0; 7.50.3 – 7.50.3; 7.50.2 – 7.50.2; 7.50.1 – 7.50.1; 7.50.0 – 7.50.0; 7.49.1 – 7.49.1; 7.49.0 – 7.49.0; 7.48.0 – 7.48.0; 7.47.1 – 7.47.1; 7.47.0 – 7.47.0; 7.46.0 – 7.46.0; 7.45.0 – 7.45.0; 7.44.0 – 7.44.0; 7.43.0 – 7.43.0; 7.42.1 – 7.42.1; 7.42.0 – 7.42.0; 7.41.0 – 7.41.0; 7.40.0 – 7.40.0; 7.39.0 – 7.39.0; 7.38.0 – 7.38.0; 7.37.1 – 7.37.1; 7.37.0 – 7.37.0; 7.36.0 – 7.36.0; 7.35.0 – 7.35.0; 7.34.0 – 7.34.0; 7.33.0 – 7.33.0; 7.32.0 – 7.32.0; 7.31.0 – 7.31.0; 7.30.0 – 7.30.0; 7.29.0 – 7.29.0; 7.28.1 – 7.28.1; 7.28.0 – 7.28.0; 7.27.0 – 7.27.0; 7.26.0 – 7.26.0; 7.25.0 – 7.25.0; 7.24.0 – 7.24.0; 7.23.1 – 7.23.1; 7.23.0 – 7.23.0; 7.22.0 – 7.22.0; 7.21.7 – 7.21.7; 7.21.6 – 7.21.6; 7.21.5 – 7.21.5; 7.21.4 – 7.21.4; 7.21.3 – 7.21.3; 7.21.2 – 7.21.2; 7.21.1 – 7.21.1; 7.21.0 – 7.21.0; 7.20.1 – 7.20.1; 7.20.0 – 7.20.0; 7.19.7 – 7.19.7; 7.19.6 – 7.19.6; 7.19.5 – 7.19.5; 7.19.4 – 7.19.4; 7.19.3 – 7.19.3; 7.19.2 – 7.19.2; 7.19.1 – 7.19.1; 7.19.0 – 7.19.0; 7.18.2 – 7.18.2; 7.18.1 – 7.18.1; 7.18.0 – 7.18.0; 7.17.1 – 7.17.1; 7.17.0 – 7.17.0; 7.16.4 – 7.16.4; 7.16.3 – 7.16.3; 7.16.2 – 7.16.2; 7.16.1 – 7.16.1; 7.16.0 – 7.16.0; 7.15.5 – 7.15.5; 7.15.4 – 7.15.4; 7.15.3 – 7.15.3; 7.15.2 – 7.15.2; 7.15.1 – 7.15.1; 7.15.0 – 7.15.0; 7.14.1 – 7.14.1; 7.14.0 – 7.14.0; 7.13.2 – 7.13.2; 7.13.1 – 7.13.1; 7.13.0 – 7.13.0; 7.12.3 – 7.12.3; 7.12.2 – 7.12.2; 7.12.1 – 7.12.1; 7.12.0 – 7.12.0; 7.11.2 – 7.11.2; 7.11.1 – 7.11.1; 7.11.0 – 7.11.0; 7.10.8 – 7.10.8 Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for curl. Red Hat fixes Red Hat Hardened Images in RHSA-2026:82895. Red Hat lists no fix planned for Red Hat Enterprise Linux 6 and none available for Red Hat Enterprise Linux 7, 8, 9 and 10, Red Hat JBoss Core Services and Red Hat Satellite 6.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
Red Hat 1 advisory
- RHSA-2026:82895 Released 2026-10-14 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images curl-8.23.0-0.1.hum1@aarch64, curl-8.23.0-0.1.hum1@s390x, curl-8.23.0-0.1.hum1@src +10
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat JBoss Core Services | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | — |
| Red Hat Satellite 6 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:82895 |
Not affected: 7 products
- Confidential Compute Attestation
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Hardened Images
- Red Hat OpenShift AI (RHOAI)
- Red Hat Satellite 6
Timeline
- 2026-10-21 Threatist record created from CVE-2026-86414
- 2026-10-21 Alias added: GHSA-6qvf-c7g3-j256
- 2026-10-30 CVSS score added · CISA ADP
- 2026-10-30 Weakness changed · CISA ADP
- 2026-10-30 CISA SSVC decision points changed
- 2026-10-30 Priority changed: LOW → HIGH
- 2026-10-31 EPSS moved to the 50th–90th percentile
- 2026-11-07 Affected versions changed · Red Hat
More curl vulnerabilities
- TI-2023-19922 Out-of-bounds write in curl CVSS 3.1CRITICAL 9.8
- 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
Sources
- CVE-2026-86414 · CVE Program
- CVE-2026-86414 · NVD
- FIRST EPSS
- GHSA-6qvf-c7g3-j256 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-86414 · 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