VulnerabilityPublished 14 Jul 2026Updated 12 Aug 2026

CVE-2026-49177: Windows TCP/IP · Out-of-bounds Read

Source GCVE Database

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Authoritative record:CVE-2026-49177· Medium 5.5

Not known to be exploited · CVSS 5.5 Medium : upgrade to 10.0.14393.9339 when convenient.

Data as of 10 Nov 2026, 23:24 UTC

CVSS 3.1 base score

5.5Medium

How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none

CVSS scores by source
CNA (microsoft)	CVSS 3.1	5.5

EPSS: 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 10.0.14393.9339, 10.0.17763.9020, 10.0.19044.7548 +8

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Base metrics

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Temporal metrics

Exploit Code Maturity: Unproven
Remediation Level: Official Fix
Report Confidence: Confirmed

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.
Exploit Code Maturity: Unproven: No exploit code is available, or an exploit is theoretical.
Remediation Level: Official Fix: A complete vendor solution is available. Either the vendor has issued an official patch, or an upgrade is available.
Report Confidence: Confirmed: Detailed reports exist, or functional reproduction is possible (functional exploits may provide this). Source code is available to independently verify the assertions of the research, or the author or vendor of the affected code has confirmed the presence of the vulnerability.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 14 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-wxj8-fwp7-7c8v

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
MicrosoftWindows 10 Version 1607	Affected >=10.0.14393.0 <10.0.14393.9339	Fixed in 10.0.14393.9339
MicrosoftWindows 10 Version 1809	Affected >=10.0.17763.0 <10.0.17763.9020	Fixed in 10.0.17763.9020
MicrosoftWindows 10 Version 21H2	Affected >=10.0.19044.0 <10.0.19044.7548	Fixed in 10.0.19044.7548
MicrosoftWindows 10 Version 22H2	Affected >=10.0.19045.0 <10.0.19045.7548	Fixed in 10.0.19045.7548
MicrosoftWindows 11 Version 24H2	Affected >=10.0.26100.0 <10.0.26100.8875	Fixed in 10.0.26100.8875
MicrosoftWindows 11 Version 25H2	Affected >=10.0.26200.0 <10.0.26200.8875	Fixed in 10.0.26200.8875

AI-suggested

No specific mitigation steps are indicated in the available data.

Description

CVE-2026-49177 is an out-of-bounds read vulnerability in the Windows TCP/IP stack that allows an authorized local attacker to disclose information. The vulnerability does not require user interaction and affects confidentiality without impacting integrity or availability.

Impact

An authorized local attacker can exploit this vulnerability to disclose sensitive information from the system memory. There is no impact on system integrity or availability. The confidentiality impact is rated high according to the CVSS vector, but the overall severity is medium due to the requirement for local privileges and no user interaction.

Summary

This vulnerability involves an out-of-bounds read in the Windows TCP/IP implementation. An attacker with local privileges can exploit this flaw to read sensitive information from memory, leading to information disclosure. The vulnerability has a CVSS 3.1 base score of 5.5, indicating a medium severity level. No public exploit code or known exploitation in the wild has been reported.

CWE-125Out-of-bounds Read (opens in a new tab)
Base weaknessCWE Top 25 (2025): #8
The product reads data past the end, or before the beginning, of the intended buffer.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design · Language Selection
Use a language that provides appropriate memory abstractions.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Overread Buffers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Nov 2026, 13:59 UTC

WeaknessesCWE-125

Technical details

References

Community reviews

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