Heap corruption via unchecked partial-character buffer writes
Published Oct 1, 2026 · Updated Oct 1, 2026
Out-of-bounds writing in Apache HTTP Server 2.4.0 through 2.4.68 allows attackers to corrupt heap memory during mod_charset_lite transcoding. In finish_partial_char, repeated incomplete conversions increment ctx->saved and append input beyond its eight-byte buffer without the bound enforced by set_aside_partial_char. The module must be configured to translate a response containing a character that remains incomplete across conversion attempts; the published advisory does not establish code execution.
Summary
What happened
Out-of-bounds writing in Apache HTTP Server 2.4.0 through 2.4.68 allows attackers to corrupt heap memory during mod_charset_lite transcoding. In finish_partial_char, repeated incomplete conversions increment ctx->saved and append input beyond its eight-byte buffer without the bound enforced by set_aside_partial_char. The module must be configured to translate a response containing a character that remains incomplete across conversion attempts; the published advisory does not establish code execution.
The record
- CVE
- CVE-2026-56153
- Published
- Oct 1, 2026
- Updated
- Oct 1, 2026
- Vendor
- The Apache Software Foundation
- Product
- Apache HTTP Server
- Classifications
- CWE-787
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 1, 2026CVE publishedPublication date reported by the CVE source.
- Oct 1, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.4.0 <=2.4.68
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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