socket.io allows an unbounded number of binary attachments
cve-program · CVE-2026-33151
PublishedSocket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Read the publisher's advisoryeuvd · EUVD-2026-13788
PublishedSocket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Read the publisher's advisorynvd · CVE-2026-33151
PublishedSocket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Read the publisher's advisoryosv · GHSA-677m-j7p3-52f9
Published### Impact A specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. ### Patches | Version range | Used by | Fixed version | |------------------|--------------------------------------------|---------------| | `>=4.0.0 <4.2.6` | `[email protected]` and `[email protected]` | `4.2.6` | | `>=3.4.0 <3.4.4` | `[email protected]` | `3.4.4` | | `<3.3.5` | `[email protected]` | `3.3.5` | ### Workarounds There is no known workaround except upgrading to a safe version. ### For more information If you have any questions or comments about this advisory: - Open a discussion [here](https://github.com/socketio/socket.io/discussions)
Read the publisher's advisoryAffected versions, risk and source history
Exploitation and risk
Source statusCISA KEV lists vulnerabilities known to be exploited. FIRST EPSS estimates the likelihood of exploitation in the next 30 days. An unavailable score does not mean zero risk.
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cve-program · CVE-2026-33151
Publishedsocket.io allows an unbounded number of binary attachments
Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
- Source published
- 20 Mar 2026 20:13:31 UTC
- Source modified
- 23 Mar 2026 16:50:16 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
euvd · EUVD-2026-13788
PublishedSocket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments a…
Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Additional publisher context
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: Mar 20, 2026, 8:13:31 PM
dateUpdated: Mar 23, 2026, 4:50:16 PM
2 related source bulletins · separate from aliases
SCA-2026-0008: Vulnerability Affecting SICK Sentio Creator Extension “Software Deployment Manager”
CVE-2026-33151
WID-SEC-W-2026-1407: IBM App Connect Enterprise Certified Container: Mehrere Schwachstellen
CVE-2026-26013 · CVE-2026-27142 · CVE-2026-28277 · CVE-2026-28684 · CVE-2026-32288 · CVE-2026-33151 · CVE-2026-33349 · CVE-2026-33532 · CVE-2026-33891 · CVE-2026-33894 · CVE-2026-33895 · CVE-2026-33896 · CVE-2026-33916 · CVE-2026-34601 · CVE-2026-35469 · CVE-2026-39406 · CVE-2026-39407 · CVE-2026-39408 · CVE-2026-39409 · CVE-2026-39410 · CVE-2026-39983 · CVE-2026-40175 · CVE-2026-40347 · CVE-2026-40895 · CVE-2026-41238 · CVE-2026-41239 · CVE-2026-41240 · CVE-2026-4923 · CVE-2026-4926
- Source published
- Mar 20, 2026, 8:13:31 PM (timezone not stated)
- Source modified
- Mar 23, 2026, 4:50:16 PM (timezone not stated)
- Saved here
- 15 Nov 2026 09:37:41 UTC
- Source terms
- ENISA EUVD · source terms and attribution apply
Original source record · Cite this exact observation · Complete original publisher JSON
Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
EUVD CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
nvd · CVE-2026-33151
PublishedSocket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments a…
Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, a specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Additional publisher context
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Analyzed
Weakness classifications: CWE-20 · CWE-754 · NVD-CWE-noinfo
Original publisher date fields
published: 2026-03-20T21:17:15.573
lastModified: 2026-06-17T10:37:02.107
1 source CPE criteria · context only
- cpe:2.3:a:socket:socket.io-parser:*:*:*:*:*:node.js:*:*
The original JSON retains the logical configuration operators, exclusions and version bounds.
- Source published
- 20 Mar 2026 21:17:15 UTC
- Source modified
- 17 Jun 2026 10:37:02 UTC
- Saved here
- 25 Oct 2026 08:17:18 UTC
- Source terms
- NIST NVD usage terms; underlying source attribution retained
Original source record · Cite this exact observation · Complete original publisher JSON
Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 4.0 · [email protected] · Secondary · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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
CVSS 3.1 · [email protected] · Primary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv · GHSA-677m-j7p3-52f9
Publishedsocket.io allows an unbounded number of binary attachments
### Impact A specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. ### Patches | Version range | Used by | Fixed version | |------------------|--------------------------------------------|---------------| | `>=4.0.0 <4.2.6` | `[email protected]` and `[email protected]` | `4.2.6` | | `>=3.4.0 <3.4.4` | `[email protected]` | `3.4.4` | | `<3.3.5` | `[email protected]` | `3.3.5` | ### Workarounds There is no known workaround except upgrading to a safe version. ### For more information If you have any questions or comments about this advisory: - Open a discussion [here](https://github.com/socketio/socket.io/discussions)
- Source published
- 18 Mar 2026 17:26:14 UTC
- Source modified
- 10 Sep 2026 03:50:37 UTC
- Saved here
- 24 Oct 2026 13:17:17 UTC
- Source terms
- GitHub Advisory Database · CC-BY-4.0
Original source record · Cite this exact observation · Complete original publisher JSON
Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Publisher rating · HIGH