A flaw was found in libsoup's SoupServer. A remote attacker could exploit a use-after-free vulnerability where the `soup_server_disconnect()` function frees connection objects prematurely, even if a TLS handshake is still pending. If the handshake completes after the connection object has been freed, a dangling pointer is accessed, leading to a server crash and a Denial of Service.
Libsoup: libsoup: denial of service via use-after-free in soupserver during tls handshake
Problem type
Affected products
Red Hat
References
https://access.redhat.com/security/cve/CVE-2026-2436
https://bugzilla.redhat.com/show_bug.cgi?id=2442909
https://gitlab.gnome.org/GNOME/libsoup/-/issues/501
GitHub Security Advisories
GHSA-wpfw-5xvc-wq9w
A flaw was found in libsoup's SoupServer. A remote attacker could exploit a use-after-free...
https://github.com/advisories/GHSA-wpfw-5xvc-wq9wA flaw was found in libsoup's SoupServer. A remote attacker could exploit a use-after-free vulnerability where the soup_server_disconnect() function frees connection objects prematurely, even if a TLS handshake is still pending. If the handshake completes after the connection object has been freed, a dangling pointer is accessed, leading to a server crash and a Denial of Service.
https://nvd.nist.gov/vuln/detail/CVE-2026-2436
https://access.redhat.com/security/cve/CVE-2026-2436
https://bugzilla.redhat.com/show_bug.cgi?id=2442909
https://gitlab.gnome.org/GNOME/libsoup/-/issues/501
https://github.com/advisories/GHSA-wpfw-5xvc-wq9w
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-2436Click to expand
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"assignerShortName": "redhat",
"dateUpdated": "2026-03-26T20:05:31.217Z",
"dateReserved": "2026-02-12T23:01:17.156Z",
"datePublished": "2026-03-26T19:31:34.270Z",
"state": "PUBLISHED"
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"datePublic": "2026-02-11T00:00:00.000Z",
"title": "Libsoup: libsoup: denial of service via use-after-free in soupserver during tls handshake",
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in libsoup's SoupServer. A remote attacker could exploit a use-after-free vulnerability where the `soup_server_disconnect()` function frees connection objects prematurely, even if a TLS handshake is still pending. If the handshake completes after the connection object has been freed, a dangling pointer is accessed, leading to a server crash and a Denial of Service."
}
],
"affected": [
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"product": "Red Hat Enterprise Linux 10",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libsoup3",
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{
"vendor": "Red Hat",
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{
"vendor": "Red Hat",
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{
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"cpes": [
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"problemTypes": [
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"type": "CWE"
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"references": [
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"url": "https://access.redhat.com/security/cve/CVE-2026-2436",
"tags": [
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{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2442909",
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"url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/501"
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"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "LOW",
"availabilityImpact": "HIGH",
"baseScore": 6.5,
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"timeline": [
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"time": "2026-02-26T01:10:12.702Z",
"lang": "en",
"value": "Reported to Red Hat."
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"time": "2026-02-11T00:00:00.000Z",
"lang": "en",
"value": "Made public."
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],
"credits": [
{
"lang": "en",
"value": "Red Hat would like to thank Ilya Rozentsvaig for reporting this issue."
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]
}
}
}