CVE-2024-6197: libcurl's ASN1 parser has this utf8asn1str() function used for parsing an ASN.1 UTF-8 string....

The vulnerability description explicitly names the utf8asn1str() function as the source of the issue. The problem is a free() call on a local stack buffer. I analyzed the provided commit information. The fixing commit 3a537a4db9e65e545ec45b1b5d5575ee09a2569d directly removes a free(buf); call from the utf8asn1str function in lib/vtls/x509asn1.c. The introducing commit 623c3a8fa0bdb2751f14b3741760d81910b7ec64 shows that buf within this function was refactored to be a stack-allocated array char buf[4]; under the conditions where the free() was later removed. This confirms that utf8asn1str is the vulnerable function, as it attempts to free a stack buffer under specific error conditions related to invalid UTF-8 character sizes.