Linux Kernel up to 7.1.8 SCTP sctp_assoc_rm_peer 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-$25k0.88

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 7.1.8. The affected element is the function sctp_assoc_rm_peer of the component SCTP. Such manipulation leads to use after free. This vulnerability is documented as CVE-2026-74688. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.1.8 and classified as very critical. Affected by this issue is the function sctp_assoc_rm_peer 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: sctp: clear control chunk transport if it is being removed sctp_make_heartbeat_ack() caches the destination transport in chunk->transport without taking a reference. When src_out_of_asoc_ok is enabled, the HEARTBEAT ACK may remain queued on control_chunk_list instead of being transmitted immediately. If the peer transport is removed while the chunk is still queued, sctp_assoc_rm_peer() drops the transport and schedules it for RCU freeing, but only clears cached transport pointers in out_chunk_list. The queued control chunk therefore retains a dangling transport pointer. Once an ASCONF_ACK clears the suppression and the queued control chunk is transmitted, SCTP dereferences the stale transport pointer, leading to a use-after-free. Fix this by also clearing chunk->transport for queued control chunks in control_chunk_list when removing the transport.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2026-74688 since 08/15/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 08/22/2026).

Upgrading to version 5.10.265, 5.15.216, 6.1.183, 6.6.152, 6.12.104, 6.18.45 or 7.1.9 eliminates this vulnerability. Applying the patch dbb3f418a8665ffb0514e1a9520ab6a1c5d4d886/fad4766a74220fe579c6fcaa10ba01c23529814f/936658ec41c28c397ef390140e02d4c91ade92f0/8de65194a04d2552cd39b6c67d942d490f22d174/6160e756db81d6cb63e3e2952efcf6c5134be385/18d704bdd809377dfd81a3c2f42426763b5da227/4d6b9cac6df5e0cfef1a66b3edd7aebdb9e4b7e7/c9158ceaf27780ef64534ad72f44ffde3f8ccc49 is able to eliminate this problem.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

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
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
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 5.10.265/5.15.216/6.1.183/6.6.152/6.12.104/6.18.45/7.1.9
Patch: dbb3f418a8665ffb0514e1a9520ab6a1c5d4d886/fad4766a74220fe579c6fcaa10ba01c23529814f/936658ec41c28c397ef390140e02d4c91ade92f0/8de65194a04d2552cd39b6c67d942d490f22d174/6160e756db81d6cb63e3e2952efcf6c5134be385/18d704bdd809377dfd81a3c2f42426763b5da227/4d6b9cac6df5e0cfef1a66b3edd7aebdb9e4b7e7/c9158ceaf27780ef64534ad72f44ffde3f8ccc49

Timelineinfo

08/15/2026 CVE reserved
08/22/2026 +7 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
08/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74688 (🔒)
GCVE (CVE): GCVE-0-2026-74688
GCVE (VulDB): GCVE-100-394466

Entryinfo

Created: 08/22/2026 18:53
Changes: 08/22/2026 18:53 (59)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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