Linux Kernel up to 7.2-rc4 sctp sctp_process_asconf_param use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k1.93+

Summaryinfo

A vulnerability classified as very critical has been found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. Affected is the function sctp_process_asconf_param of the component sctp. The manipulation leads to use after free. This vulnerability is traded as CVE-2026-64564. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. This issue affects the function sctp_process_asconf_param of the component sctp. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: sctp: don't free the ASCONF's own transport in DEL-IP processing sctp_process_asconf() caches the transport the ASCONF chunk is processed against in asconf->transport (== chunk->transport, set once in sctp_rcv()). For an ASCONF located through its Address Parameter by __sctp_rcv_asconf_lookup(), that cached transport corresponds to the Address Parameter, which need not be the packet's source address. sctp_process_asconf_param() rejects a DEL-IP for the packet source address (ADDIP D8, SCTP_ERROR_DEL_SRC_IP), but nothing protects asconf->transport. A single ASCONF can therefore carry, in order: [Address Parameter L] [DEL-IP L] [DEL-IP 0.0.0.0] where L differs from the source. The DEL-IP for L passes the D8 check and calls sctp_assoc_rm_peer() on the transport that asconf->transport still points at, freeing it (RCU-deferred). The following wildcard DEL-IP then reuses the now-dangling asconf->transport in sctp_assoc_set_primary() and sctp_assoc_del_nonprimary_peers(): set_primary() dereferences the freed transport (->ipaddr, ->state) and plants the dangling pointer into asoc->peer.primary_path / active_path, and del_nonprimary_peers(), keeping only the pointer that is no longer on the list, removes every real transport, leaving the association with a transport_count of 0 and primary_path/active_path pointing at freed memory. Reject a DEL-IP that targets the transport the ASCONF is being processed against, mirroring the existing source-address guard, so the wildcard branch can never reuse a freed transport.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-64564 since 07/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/04/2026).

Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch fedeb4468987bcaff85fe3061de5ae052d414740/74e8f3e7114f0e26d1b2c4c048044db9fcc27603/85aca407c560aba81b5ce9d3d6cf94c74077d19b/d136b29bf91dd8e3161281b87de597b7311d9462/9b2854f86f0b56e9027d68e7a3fc909d1a9b566f is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-52605). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: fedeb4468987bcaff85fe3061de5ae052d414740/74e8f3e7114f0e26d1b2c4c048044db9fcc27603/85aca407c560aba81b5ce9d3d6cf94c74077d19b/d136b29bf91dd8e3161281b87de597b7311d9462/9b2854f86f0b56e9027d68e7a3fc909d1a9b566f

Timelineinfo

07/19/2026 CVE reserved
08/04/2026 +16 days Advisory disclosed
08/04/2026 +0 days VulDB entry created
08/04/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64564 (🔒)
GCVE (CVE): GCVE-0-2026-64564
GCVE (VulDB): GCVE-100-385769
EUVD: 🔒

Entryinfo

Created: 08/04/2026 09:04
Updated: 08/04/2026 09:16
Changes: 08/04/2026 09:04 (59), 08/04/2026 09:16 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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