VulnerabilityPublished 10 Nov 2026

CVE-2026-125334: Forge · TLS client crash on a handshake record received without a session

Affects node-forgeSource GCVE Database

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Authoritative record:CVE-2026-125334· Medium 5.9

Not known to be exploited · CVSS 5.9 Medium : upgrade to 1.4.3 when convenient.

Data as of 10 Nov 2026, 22:34 UTC

CVSS 3.1 base score

5.9Medium

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

Thin evidence

One scorer or none

CVSS scores by source
CNA (GitHub_M)	CVSS 3.1	5.9

Patch: Available – fixed in 1.4.3

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

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

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 10 Nov 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 10 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.

What to do

Upgrade node-forge to 1.4.3.

Affected software

Product	Affected	Fixed in
npmnode-forge	Affected <1.4.3	Fixed in 1.4.3

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Description

### Summary A `forge.tls` client throws an uncaught `TypeError` from `connection.process()` when it receives a ServerHello while it has no session: after a `close_notify` alert or a call to `close()`, or before `handshake()` is called. A malicious server or an on-path attacker can use this to terminate a Node.js process. Fixed in node-forge 1.4.3. ### Details `tls.handleHandshake()` in `lib/tls.js` updates the handshake digests with `c.session.md5.update(bytes)` before it calls the message handler. A client creates its session in `handshake()`, and `c.reset()` sets it to `null` when the connection is closed. Closing doesn't set the fail flag, and the client goes back to expecting a ServerHello, so a Handshake record received afterwards still reaches `handleHandshake()`, which throws `TypeError: Cannot read properties of null (reading 'md5')`. This happens: - after the server sends a `close_notify` alert (at any alert level); - after the application calls `close()`; - before the application calls `handshake()`. The exception propagates out of `connection.process()`. Applications that pass socket data to `process()` from a `data` event handler without catching exceptions, as in the README example, terminate. After a reset the connection uses no encryption, so an on-path attacker can inject the records even when the real server is honest. Servers are not affected: a server creates its session when it receives a ClientHello. The fix handles these records like other unexpected records on a closed client: they are ignored. #### Patches Fixed in node-forge 1.4.3. #### Workarounds Catch exceptions thrown by `connection.process()` and close the socket, or stop passing socket data to `process()` once the `closed` callback has been called and until `handshake()` is called again. #### Resources - RFC 5246, section 7.2.1 (Closure Alerts): https://www.rfc-editor.org/rfc/rfc5246#section-7.2.1 - Related: GHSA-525v-9gp9-w22h (another TLS client `TypeError`, fixed in 1.4.1): https://github.com/digitalbazaar/forge/security/advisories/GHSA-525v-9gp9-w22h #### Severity CVSS 3.1: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H (5.9, Moderate) CVSS 4.0 (informational): CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N (8.2) CVSS 4.0 has no counterpart to 3.1's AC:H beyond AT:P and scores this higher; the severity rating follows CVSS 3.1. #### Credits Reported by @manus-use. ### Proof of concept var c = forge.tls.createConnection({server: false, ...}); c.handshake(); // warning close_notify alert, then an empty ServerHello, in separate // process() calls c.process(forge.util.hexToBytes('15030100020100')); c.process(forge.util.hexToBytes('160301000402000000')); // <= 1.4.2: TypeError: Cannot read properties of null (reading 'md5') // 1.4.3: the record is ignored The reporter's PoC is in tests/pocs/ghsa-j8rw-jp99-435v.js, and regression tests are in tests/unit/tls.js. ### Impact Applications that use `forge.tls` as a client and pass data from a network socket to `connection.process()` are affected. The server they connect to, or an on-path attacker, can make `process()` throw; if the application doesn't catch it, the Node.js process terminates, dropping all its connections. Servers built on `forge.tls` are not affected. There is no confidentiality or integrity impact.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

WeaknessesCWE-476

Technical details

References

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