guzzlehttp/guzzle versions before 7.15.1 contain a denial of service vulnerability in the CookieJar that accepts unlimited Set-Cookie header fields with no size restrictions. Attackers can return many large cookies from a malicious server, causing Guzzle to store excessive data in memory and generate oversized Cookie headers that fail in handlers or destination servers.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-770"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67353.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "7.15.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"introduced": "0"
},
{
"fixed": "7.15.1"
}
],
"source": "DESCRIPTION"
}
]
}