Memory corruption via Unicode conversion integer overflow
Published Jan 27, 2026 · Updated Jan 27, 2026
Out-of-bounds writes in GLib on Red Hat Enterprise Linux 6 through 10 allow remote attackers to corrupt memory via large Unicode input. The output_marks() and real_tolower() paths mix signed and unsigned types when sizing a UTF-8 conversion buffer, causing integer wraparound, an undersized heap allocation, and writes past its end. Exploitation requires an application to process attacker-controlled, extremely large Unicode strings; reported consequences are a crash, instability, and memory corruption.
Summary
What happened
Out-of-bounds writes in GLib on Red Hat Enterprise Linux 6 through 10 allow remote attackers to corrupt memory via large Unicode input. The output_marks() and real_tolower() paths mix signed and unsigned types when sizing a UTF-8 conversion buffer, causing integer wraparound, an undersized heap allocation, and writes past its end. Exploitation requires an application to process attacker-controlled, extremely large Unicode strings; reported consequences are a crash, instability, and memory corruption.
The record
- CVE
- CVE-2026-1489
- Published
- Jan 27, 2026
- Updated
- Jan 27, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Enterprise Linux 6
- Classifications
- CWE-787
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 27, 2026CVE publishedPublication date reported by the CVE source.
- Jan 27, 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?
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What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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