libclamav: Harden XLM formula record parsing - #1783
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val-ms merged 2 commits intoAug 7, 2026
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Validate XLM formula record sizes before parsing and honor the declared token-stream length instead of parsing all trailing record data. Correct the FORMULA record accounting and add bounds checks for token operands, strings, attributes, function arguments, and cell references. Malformed or truncated tokens now terminate parsing without consuming data beyond the declared formula buffer. Add unit and clamscan regression tests covering boundary-length records, truncated tokens, malformed strings, and scan-map edge cases. Reported by Alessandro Greco (GitHub user 'aleff-github'). CLAM-3011
val-ms
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Jul 30, 2026
Add a valid ptgStr regression case and use a signature matching its disassembled output to verify detection through clamscan and scan-map. Flush the extracted XLM stream before scanning so buffered formula output is visible to the scanner. CLAM-3011
val-ms
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Aug 7, 2026
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Code looks good and local testing went well. I'm waiting for it to run through Jenkins, but I'm happy with it.
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Validate XLM formula record sizes before parsing and honor the declared token-stream length instead of parsing all trailing record data.
Correct the FORMULA record accounting and add bounds checks for token operands, strings, attributes, function arguments, and cell references. Malformed or truncated tokens now terminate parsing without consuming data beyond the declared formula buffer.
Add unit and clamscan regression tests covering boundary-length records, truncated tokens, malformed strings, and scan-map edge cases.
Reported by Alessandro Greco (GitHub user 'aleff-github').
CLAM-3011