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CVE-2026-11856

cross-origin Digest auth state leak

Published: Jul 3, 2026Updated: Jul 7, 2026 Sources: CVE List NVDCWE-294
9.8CRITICAL
NVD MITRE
EPSS Score
0.6%
Top 54.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Successfully using libcurl to do a transfer to a specific HTTP origin (`hostA`) with **Digest** authentication and then changing the origin to a different one (`hostB`) for a second transfer, reusing the same handle, makes libcurl wrongly pass on the `Authorization:` header field meant for `hostA`, to `hostB`.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-294

Affected Products

haxx
oss-project·SEaka haxx.se
curl
OSS Libraries
curl
oss-project·USaka libcurl, wcurl
curlLibraryLibrary
OSS Libraries / generic-library

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Defense Evasion
View detailed technique mapping

References

https://curl.se/docs/CVE-2026-11856.html
curl.se
https://curl.se/docs/CVE-2026-11856.json
curl.se
https://hackerone.com/reports/3793260
hackerone.com
News mentions
1

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