secure cookie attribute bypass with tab
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Partial Red Hat: 1 fixed, 1 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-201.
Summary
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
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 | 8.13.0 to before 8.14.2; 8.15.0 to before 8.16.1; 8.17.0 to before 8.20.1; 8.21.0 to before 8.22.0 | 8.14.2, 8.16.1, 8.20.1, 8.22.0 | Patch available | CNA |
| curl | curl | 8.21.0; 8.20.0; 8.19.0; 8.18.0; 8.17.0; 8.16.0; 8.15.0; 8.14.1; 8.14.0; 8.13.0 | — | No fix listed | CNA |
- curl Vendorcurl Affected 8.13.0 to before 8.14.2; 8.15.0 to before 8.16.1; 8.17.0 to before 8.20.1; 8.21.0 to before 8.22.0 Fixed in 8.14.2, 8.16.1, 8.20.1, 8.22.0 Patch available CNA
- curl Vendorcurl Affected 8.21.0; 8.20.0; 8.19.0; 8.18.0; 8.17.0; 8.16.0; 8.15.0; 8.14.1; 8.14.0; 8.13.0 Fixed in — No fix listed CNA
Remediation
- Fix · CNA curl (curl) Fixed in 8.14.2, 8.16.1, 8.20.1, 8.22.0
Red Hat 1 advisory
- RHSA-2026:63161 Released 2026-09-03 · Red Hat rating ModerateRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images curl-8.22.0-0.1.hum1@aarch64, curl-8.22.0-0.1.hum1@src, curl-8.22.0-0.1.hum1@x86_64 +6
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
curl 8.14.2, 8.16.1 and 2 more versions
9 records Highest priority Priority HIGH 8 HIGH, 1 MEDIUM
Other records, highest priority first
- TI-2026-16162 Negotiate ambient user conn reusePriority HIGH 82
- TI-2026-15472 HTTP/2 server push UAFPriority HIGH 78
- TI-2026-56683 domain-scoped PSL domain cookiePriority HIGH 75
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Satellite 6 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:63161 |
Not affected: 12 products
- Confidential Compute Attestation
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat JBoss Core Services
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
- Red Hat OpenShift Dev Spaces
- Red Hat Satellite 6
Timeline
- 2026-10-02 Threatist record created from CVE-2026-80255
- 2026-10-03 Alias added: GHSA-vmmm-3jqx-jgx8
- 2026-10-30 Affected versions changed · Red Hat
References
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-2026-80255 · CVE Program
- CVE-2026-80255 · NVD
- FIRST EPSS
- GHSA-vmmm-3jqx-jgx8 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-80255 · 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