CVE-2024-6197: freeing stack buffer in utf8asn1str
cURL libcurl is vulnerable to a denial of service, caused by a memory allocation flaw in the utf8asn1str() function in the ASN1 parser. By using a specially crafted TLS certificate, a remote attacker could exploit this vulnerability to cause a denial of service condition.
Other sources
Hackerone: CVE-2024-6197 Freeing stack buffer in utf8asn1str
— Microsoft
libcurl's ASN1 parser has this utf8asn1str() function used for parsing an ASN.1 UTF-8 string. Itcan detect an invalid field and return error. Unfortunately, when doing so it also invokes free() on a 4 byte localstack buffer. Most modern malloc implementations detect this error and immediately abort. Some however accept the input pointer and add that memory to its list of available chunks. This leads to the overwriting of nearby stack memory. The content of the overwrite is decided by the free() implementation; likely to be memory pointers and a set of flags. The most likely outcome of exploting this flaw is a crash, although it cannot be ruled out that more serious results can be had in special circumstances.
— MITRE
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2024-6197?
CVE-2024-6197 has a severity rating that classifies it as a denial of service vulnerability.
How do I fix CVE-2024-6197?
To fix CVE-2024-6197, apply the relevant patches or updates provided by your operating system vendor or software provider.
Which software is affected by CVE-2024-6197?
CVE-2024-6197 affects various versions of Microsoft Windows, Windows Server, cURL, and IBM Storage Protect Backup-Archive Client.
Can CVE-2024-6197 be exploited remotely?
Yes, CVE-2024-6197 can be exploited remotely if a specially crafted TLS certificate is used by an attacker.
What impact does CVE-2024-6197 have on systems?
The impact of CVE-2024-6197 includes the potential for a denial of service, rendering affected systems unavailable.