Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NSummary
CVE-2026-8926 is a critical-severity Insufficiently Protected Credentials (CWE-522) vulnerability in Haxx Curl. Its CVSS base score is 9.1 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Credentials In Files (T1552.001); ranked at the 30th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-41507
Vulnerability Data
When asking curl to use a `.netrc` file to find credentials and at the same time specifying a URL with a username(without a password), like `https://user@example.com/`, curl could wrongly get and use the password for *another* user set in the…
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`.netrc` file for that host if such a one exists and there is no match for the specified user.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Logic flaw in .netrc credential lookup enables misuse of valid credentials from local file when URL specifies username.
Likely ATT&CK TechniquesAI
Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
Least-privilege enforcement of credential selection prevents curl from retrieving and applying a password belonging to a different user than the one explicitly named in the URL.
Access-enforcement logic must ensure that only the exact username supplied in the URL is matched against the .netrc file, blocking unauthorized credential substitution.
Integrity verification of the authentication flow can detect when an incorrect credential pair is selected from the .netrc file for the given user.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Encrypting data-at-rest fully prevents insecure credential storage while only partially satisfying the broader data-protection outcome.
Encrypting data-in-transit fully prevents interception of credentials in motion while only partially satisfying the broader data-protection outcome.
Credential management practices directly reduce insecure storage/transmission but do not guarantee encryption or transport protection.
Protecting identity assertions covers conveyance of credentials but is narrower than full credential lifecycle protection.
Authentication policies can enforce stronger credential handling yet address only verification, not storage or transit protection.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Requiring protected storage, transmission, and non-display of passwords prevents credentials from being stored or sent in clear text where they can be harvested by unauthorized actors.
Protecting secret and private keys against disclosure and unauthorized use decreases the exposure of credentials that are stored or transmitted in recoverable form.
Forbidding clear-text transmission and display of passwords, plus the use of stronger alternatives to passwords, prevents credentials from being obtained or reused by attackers.
Acceptable-use expectations that cover protection of credentials and information assets throughout their lifecycle discourage practices that expose or mishandle authentication material.
Contractual clauses that survive termination help ensure that credentials and other secrets are not retained or misused after employment ends.
Regular reminders about password security and personal accountability make users less likely to store or transmit credentials in cleartext or other unprotected forms.