schannel_verify: avoid out of blob access#21543
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The code would previously read one byte past the provided CURLOPT_CAINFO_BLOB if the blob ends exactly with -----BEGIN CERTIFICATE----- Reported-by: Andrew Nesbit
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Pull request overview
Fixes a bounds-read in Schannel certificate blob parsing when a CURLOPT_CAINFO_BLOB ends exactly with the -----BEGIN CERTIFICATE----- marker, preventing a 1-byte out-of-bounds access during newline validation.
Changes:
- Adjusts the
c_memmem()search length to guarantee there is at least one byte available after aBEGIN_CERTmatch before inspecting it. - Replaces a local newline helper with the shared
ISNEWLINE()macro.
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The code would previously read one byte past the provided CURLOPT_CAINFO_BLOB if the blob ends exactly with -----BEGIN CERTIFICATE----- Reported-by: Andrew Nesbit Closes curl#21543
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The code would previously read one byte past the provided CURLOPT_CAINFO_BLOB if the blob ends exactly with -----BEGIN CERTIFICATE-----
Reported-by: Andrew Nesbit