System memory exhaustion via unbounded stdin read
Published Mar 26, 2026 · Updated Mar 26, 2026
Denial of service in Red Hat polkit allows local users to exhaust system memory through polkit-agent-helper-1 standard input. The read_cookie function calls getline on the cookie stream without a length cap and performs the non-TTY check only after allocation. Any local user can execute the mode-04755 helper through a pipe; systems using only the socket-activated helper are not exposed.
Summary
What happened
Denial of service in Red Hat polkit allows local users to exhaust system memory through polkit-agent-helper-1 standard input. The read_cookie function calls getline on the cookie stream without a length cap and performs the non-TTY check only after allocation. Any local user can execute the mode-04755 helper through a pipe; systems using only the socket-activated helper are not exposed.
The record
- CVE
- CVE-2026-4897
- Published
- Mar 26, 2026
- Updated
- Mar 26, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Enterprise Linux 6
- Classifications
- CWE-770, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 26, 2026CVE publishedPublication date reported by the CVE source.
- Mar 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Red Hat Bugzilla local OOM proof of conceptproof of concept · unverified
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Technologies
Your stack
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Your stack
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