CVE-2026-29007
U-Boot 2026.04-rc3 Out-of-Bounds Read in tcp_rx_state_machine via tcp.c
Description
U-Boot through 2026.04-rc3 contains an out-of-bounds read vulnerability in tcp_rx_state_machine() (net/tcp.c) when CONFIG_PROT_TCP is enabled, allowing remote attackers to read beyond TCP segment boundaries by crafting a malicious packet with a mismatched IP total length and TCP data offset field. Attackers can send a packet with an IP total length of 40 bytes and a TCP data offset claiming 60 bytes of header to cause tcp_parse_options() to read 40 bytes past the end of the TCP segment, potentially corrupting connection state variables such as rmt_win_scale and rmt_timestamp to disrupt TCP window calculations.
INFO
Published Date :
July 8, 2026, 5:17 p.m.
Last Modified :
July 22, 2026, 6:31 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update U-Boot to a version later than 2026.04-rc3.
- Disable CONFIG_PROT_TCP if updating is not possible.
- Sanitize network packet header fields.
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-2026-29007.
| URL | Resource |
|---|---|
| https://lists.denx.de/pipermail/u-boot/2026-May/617853.html | Mailing List Third Party Advisory |
| https://u-boot.org/ | Product |
| https://www.vulncheck.com/advisories/u-boot-rc3-out-of-bounds-read-in-tcp-rx-state-machine-via-tcp-c | Third Party Advisory Exploit |
| https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/ | Third Party Advisory Exploit |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-29007 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-2026-29007
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-2026-29007 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-29007 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.
-
Initial Analysis by [email protected]
Jul. 22, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:denx:u-boot:2026.04:rc1:*:*:*:*:*:* *cpe:2.3:a:denx:u-boot:2026.04:rc2:*:*:*:*:*:* *cpe:2.3:a:denx:u-boot:2026.04:rc3:*:*:*:*:*:* *cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:* versions up to (excluding) 2026.04 Added Reference Type VulnCheck: https://lists.denx.de/pipermail/u-boot/2026-May/617853.html Types: Mailing List, Third Party Advisory Added Reference Type VulnCheck: https://u-boot.org/ Types: Product Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/u-boot-rc3-out-of-bounds-read-in-tcp-rx-state-machine-via-tcp-c Types: Exploit, Third Party Advisory Added Reference Type VulnCheck: https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/ Types: Exploit, Third Party Advisory -
CVE Modified by [email protected]
Jul. 14, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://github.com/u-boot/u-boot', 'vendor': 'u-boot', 'product': 'u-boot', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '2026.04-rc3'}], 'defaultStatus': 'affected'}] [{'repo': 'https://github.com/u-boot/u-boot', 'vendor': 'u-boot', 'product': 'u-boot', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '2026.04-rc3'}], 'packageURL': 'pkg:github/u-boot/u-boot', 'defaultStatus': 'affected'}] -
CVE Modified by [email protected]
Jul. 13, 2026
Action Type Old Value New Value Added Reference https://y637f9qq2x.com/posts/u-boot-tcp-nfs-vulns/ -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 08, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-29007', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-08T19:43:17.211226Z'} -
New CVE Received by [email protected]
Jul. 08, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/u-boot/u-boot', 'vendor': 'u-boot', 'product': 'u-boot', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '2026.04-rc3'}], 'defaultStatus': 'affected'}] Added Description U-Boot through 2026.04-rc3 contains an out-of-bounds read vulnerability in tcp_rx_state_machine() (net/tcp.c) when CONFIG_PROT_TCP is enabled, allowing remote attackers to read beyond TCP segment boundaries by crafting a malicious packet with a mismatched IP total length and TCP data offset field. Attackers can send a packet with an IP total length of 40 bytes and a TCP data offset claiming 60 bytes of header to cause tcp_parse_options() to read 40 bytes past the end of the TCP segment, potentially corrupting connection state variables such as rmt_win_scale and rmt_timestamp to disrupt TCP window calculations. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-125 Added Reference https://lists.denx.de/pipermail/u-boot/2026-May/617853.html Added Reference https://u-boot.org/ Added Reference https://www.vulncheck.com/advisories/u-boot-rc3-out-of-bounds-read-in-tcp-rx-state-machine-via-tcp-c