CVE-2026-2967
published 2026-02-23CVE-2026-2967: A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component…
PriorityP420low3.7CVSS 3.1
AVNACHPRNUINSUCNINAL
EPSS
0.49%
38.5th percentile
A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Affected
22 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cesanta | mongoose | <= 7.20 | — |
| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
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| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
| cesanta | mongoose | — | — |
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CVSS provenance
nvdv3.13.7LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
nvdv4.02.9LOWCVSS: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/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
nvdv2.02.6LOWAV:N/AC:H/Au:N/C:N/I:N/A:P
osv6.3MEDIUM
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OSV
CVE-2026-2967: A security vulnerability has been detected in Cesanta Mongoose up to 7
osv·2026-02-23·CVSS 6.3
CVE-2026-2967 [MEDIUM] CVE-2026-2967: A security vulnerability has been detected in Cesanta Mongoose up to 7
A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
GHSA
GHSA-c6h3-vh8h-r8mj: A security vulnerability has been detected in Cesanta Mongoose up to 7
ghsa_unreviewed·2026-02-23
CVE-2026-2967 [MEDIUM] CWE-940 GHSA-c6h3-vh8h-r8mj: A security vulnerability has been detected in Cesanta Mongoose up to 7
A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-2967 mongoose: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
bugzilla·2026-02-23·CVSS 2.9
CVE-2026-2967 [LOW] CVE-2026-2967 mongoose: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
CVE-2026-2967 mongoose: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '42'.
Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained vers
Bugzilla
CVE-2026-2967 smplayer: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
bugzilla·2026-02-23·CVSS 2.9
CVE-2026-2967 [LOW] CVE-2026-2967 smplayer: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
CVE-2026-2967 smplayer: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '42'.
Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained vers
Bugzilla
CVE-2026-2967 flmsg: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
bugzilla·2026-02-23·CVSS 2.9
CVE-2026-2967 [LOW] CVE-2026-2967 flmsg: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
CVE-2026-2967 flmsg: Mongoose: Remote Denial of Service in TCP Sequence Number Handler [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '42'.
Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version
Wiz
CVE-2026-2967 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 6.3
CVE-2026-2967 [MEDIUM] CVE-2026-2967 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-2967 :
NixOS vulnerability analysis and mitigation
A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Source : NVD
## 6.3
Score
Published February 23, 2026
Severity MEDIUM
CNA Score 6.3
Affected Technologies
NixOS
Homebrew
Has Public Exploit Yes
Has CISA KEV Exploit No
CISA KEV Relea
2026-02-23
Published