{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-15709", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-07-14T09:32:47.038Z", "datePublished": "2026-07-14T19:41:37.331Z", "dateUpdated": "2026-07-14T19:41:37.331Z"}, "containers": {"cna": {"title": "Soupwebsocketextensiondeflate: libsoup: libsoup: websocket permessage-deflate unbounded decompression remote denial of service", "metrics": [{"other": {"content": {"value": "Moderate", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary limit on the output buffer size. While libsoup limits the incoming compressed frame size via max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate check for decompressed size (max_total_message_size) exists but executes only after inflation is complete, and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service (DoS)."}], "affected": [{"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libsoup3", "defaultStatus": "affected", "cpes": ["cpe:/o:redhat:enterprise_linux:10"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 6", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libsoup", "defaultStatus": "unknown", "cpes": ["cpe:/o:redhat:enterprise_linux:6"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 7", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libsoup", "defaultStatus": "unknown", "cpes": ["cpe:/o:redhat:enterprise_linux:7"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libsoup", "defaultStatus": "affected", "cpes": ["cpe:/o:redhat:enterprise_linux:8"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libsoup", "defaultStatus": "affected", "cpes": ["cpe:/o:redhat:enterprise_linux:9"]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-15709", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499922", "name": "RHBZ#2499922", "tags": ["issue-tracking", "x_refsource_REDHAT"]}, {"url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/511"}], "datePublic": "2026-07-14T09:42:00.000Z", "problemTypes": [{"descriptions": [{"cweId": "CWE-409", "description": "Improper Handling of Highly Compressed Data (Data Amplification)", "lang": "en", "type": "CWE"}]}], "x_redhatCweChain": "CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)", "workarounds": [{"lang": "en", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}], "timeline": [{"lang": "en", "time": "2026-07-14T09:34:32.593Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-07-14T09:42:00.000Z", "value": "Made public."}], "credits": [{"lang": "en", "value": "Red Hat would like to thank Tristan Madani for reporting this issue."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-07-14T19:41:37.331Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}}}

{}

{}

{"acknowledgement": "Red Hat would like to thank Tristan Madani for reporting this issue.", "bugzilla": {"description": "SoupWebsocketExtensionDeflate: libsoup: libsoup: WebSocket permessage-deflate Unbounded Decompression Remote Denial of Service", "id": "2499922", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499922"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-409", "details": ["A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary limit on the output buffer size. While libsoup limits the incoming compressed frame size via max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate check for decompressed size (max_total_message_size) exists but executes only after inflation is complete, and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service (DoS)."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}, "name": "CVE-2026-15709", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "libsoup3", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "libsoup", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "libsoup", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "libsoup", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "libsoup", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-07-14T09:42:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-15709\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-15709\nhttps://gitlab.gnome.org/GNOME/libsoup/-/issues/511"], "statement": "This vulnerability poses a high availability risk to both clients and servers utilizing libsoup for WebSocket communication. Because the memory exhaustion occurs during the extraction process before payload size validations are applied, standard post-decompression limits fail to mitigate the threat. A network-based attacker requires no privileges or user interaction to deliberately crash vulnerable applications or desktop services that establish connections using the default permessage-deflate configuration.", "threat_severity": "Moderate"}