7.5
HIGH
CVSS 3.1
CVE-2026-74282
tipc: prevent snt_unacked underflow on CONN_ACK
Overview
Description
In the Linux kernel, the following vulnerability has been resolved: tipc: prevent snt_unacked underflow on CONN_ACK tipc_sk_conn_proto_rcv() subtracts the peer-supplied connection ack count from the unsigned 16-bit send counter snt_unacked without checking that it does not exceed the number of messages actually outstanding: tsk->snt_unacked -= msg_conn_ack(hdr); msg_conn_ack() is read straight from a received CONN_MANAGER/CONN_ACK message. If the ack count is larger than snt_unacked, the subtraction wraps to a near-maximum value, leaving tsk_conn_cong() permanently true and starving the connection of further transmits. Validate the ACK count at the start of the CONN_ACK block and drop the message if it acknowledges more messages than are outstanding. A peer (or, for a local connection, the connected peer socket) can otherwise wedge a TIPC connection's send side by sending an oversized connection ack.
Details
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 17, 2026, 6:19 a.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Scoring
CVSS Scores
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for assessing the severity of vulnerabilities in software and systems.
We collect and displays CVSS scores from various sources for each CVE.
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
Address tipc underflow by validating ACK counts to prevent connection hangs.
- Validate ACK count against outstanding messages.
- Drop oversized ACK messages.
- Apply the Linux kernel patch.
References
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74282.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74282 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74282
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74282 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74282 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3388145d258cf2c4c98278e3987296007d30672e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '67e55b054bf8025658dc0e255057f2a6236416bd', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '96f91b8ae1a489b3eca137e7acf42cf985fb8939', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '47ed873e4ceda34098bd46d8e96b4bb13cad3a04', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'b44bebdd32c9ff66ee2aebfc317ced44bedd9335', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3cfa3d8e0dc167850edeb5bf5a07757db83fd54e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '1e2c956745777e6ffdee7f30da5935741c03ee1e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'ab3e10b44ba5411779aac7afd2477917dd77750f', 'versionType': 'git'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3388145d258cf2c4c98278e3987296007d30672e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '67e55b054bf8025658dc0e255057f2a6236416bd', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '96f91b8ae1a489b3eca137e7acf42cf985fb8939', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '47ed873e4ceda34098bd46d8e96b4bb13cad3a04', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'b44bebdd32c9ff66ee2aebfc317ced44bedd9335', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3cfa3d8e0dc167850edeb5bf5a07757db83fd54e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '1e2c956745777e6ffdee7f30da5935741c03ee1e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'ab3e10b44ba5411779aac7afd2477917dd77750f', 'versionType': 'git'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3388145d258cf2c4c98278e3987296007d30672e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '67e55b054bf8025658dc0e255057f2a6236416bd', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '96f91b8ae1a489b3eca137e7acf42cf985fb8939', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '47ed873e4ceda34098bd46d8e96b4bb13cad3a04', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'b44bebdd32c9ff66ee2aebfc317ced44bedd9335', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '3cfa3d8e0dc167850edeb5bf5a07757db83fd54e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': '1e2c956745777e6ffdee7f30da5935741c03ee1e', 'versionType': 'git'}, {'status': 'affected', 'version': '10724cc7bb7832b482df049c20fd824d928c5eaa', 'lessThan': 'ab3e10b44ba5411779aac7afd2477917dd77750f', 'versionType': 'git'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/socket.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: tipc: prevent snt_unacked underflow on CONN_ACK tipc_sk_conn_proto_rcv() subtracts the peer-supplied connection ack count from the unsigned 16-bit send counter snt_unacked without checking that it does not exceed the number of messages actually outstanding: tsk->snt_unacked -= msg_conn_ack(hdr); msg_conn_ack() is read straight from a received CONN_MANAGER/CONN_ACK message. If the ack count is larger than snt_unacked, the subtraction wraps to a near-maximum value, leaving tsk_conn_cong() permanently true and starving the connection of further transmits. Validate the ACK count at the start of the CONN_ACK block and drop the message if it acknowledges more messages than are outstanding. A peer (or, for a local connection, the connected peer socket) can otherwise wedge a TIPC connection's send side by sending an oversized connection ack. Added Reference https://git.kernel.org/stable/c/1e2c956745777e6ffdee7f30da5935741c03ee1e Added Reference https://git.kernel.org/stable/c/3388145d258cf2c4c98278e3987296007d30672e Added Reference https://git.kernel.org/stable/c/3cfa3d8e0dc167850edeb5bf5a07757db83fd54e Added Reference https://git.kernel.org/stable/c/47ed873e4ceda34098bd46d8e96b4bb13cad3a04 Added Reference https://git.kernel.org/stable/c/67e55b054bf8025658dc0e255057f2a6236416bd Added Reference https://git.kernel.org/stable/c/96f91b8ae1a489b3eca137e7acf42cf985fb8939 Added Reference https://git.kernel.org/stable/c/ab3e10b44ba5411779aac7afd2477917dd77750f Added Reference https://git.kernel.org/stable/c/b44bebdd32c9ff66ee2aebfc317ced44bedd9335
EPSS is a daily estimate of the probability of exploitation activity
being observed over the next 30 days. Following chart shows the EPSS
score history of the vulnerability.