CVE-2026-2967Public exploitNetwork attack vector

Remote session termination via unchecked TCP RST

Published Feb 23, 2026 · Updated Feb 23, 2026

Denial of service in Cesanta Mongoose 7.0 through 7.20 allows remote attackers to terminate TCP sessions via forged RST packets. The MIP getpeer function associates incoming segments with connections by port pair without checking source IP, and rx_tcp accepts RSTs without validating sequence numbers. Exploitation requires the built-in TCP/IP stack and knowledge or guessing of the active port pair; one spoofed packet closes the matched session without affecting confidentiality or integrity.

CVSS severity3.7
Low
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cesanta Mongoose 7.0 through 7.20 allows remote attackers to terminate TCP sessions via forged RST packets. The MIP getpeer function associates incoming segments with connections by port pair without checking source IP, and rx_tcp accepts RSTs without validating sequence numbers. Exploitation requires the built-in TCP/IP stack and knowledge or guessing of the active port pair; one spoofed packet closes the matched session without affecting confidentiality or integrity.

The record

CVE
CVE-2026-2967
Published
Feb 23, 2026
Updated
Feb 23, 2026
Vendor
Cesanta
Product
Mongoose
Classifications
CWE-940, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.0
  2. Affected versionversion=7.1
  3. Affected versionversion=7.10
  4. Affected versionversion=7.11
  5. Affected versionversion=7.12
  6. Affected versionversion=7.13
  7. Affected versionversion=7.14
  8. Affected versionversion=7.15
  9. Affected versionversion=7.16
  10. Affected versionversion=7.17
  11. Affected versionversion=7.18
  12. Affected versionversion=7.19
  13. Affected versionversion=7.2
  14. Affected versionversion=7.20
  15. Affected versionversion=7.3
  16. Affected versionversion=7.4
  17. Affected versionversion=7.5
  18. Affected versionversion=7.6
  19. Affected versionversion=7.7
  20. Affected versionversion=7.8
  21. Affected versionversion=7.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cesanta · Mongooseversion=7.0; version=7.1; version=7.10; version=7.11; version=7.12; version=7.13; version=7.14; version=7.15; version=7.16; version=7.17; version=7.18; version=7.19; version=7.2; version=7.20; version=7.3; version=7.4; version=7.5; version=7.6; version=7.7; version=7.8; version=7.9

Published CVSS scores

2.6VulDBAV:N/AC:H/Au:N/C:N/I:N/A:P
2.9VulDBCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
3.7VulDBCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-940Improper Verification of Source of a Communication Channel
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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