VulnerabilityPublished 13 Mar 2026Updated 16 Mar 2026

CVE-2026-32614: emmansun gmsm · Improper Verification of Cryptographic Signature

Affects emmansun gmsmSource CVE Database V5

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Not known to be exploited · CVSS 7.5 High : upgrade to 0.41.1 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 0.41.1

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

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

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: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 13 Mar 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 30 Oct 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 gmsm and github.com/emmansun/gmsm to 0.41.1.

Affected software

Product	Affected	Fixed in
emmansungmsm	Affected <0.41.1	Fixed in 0.41.1
Gogithub.com/emmansun/gmsm`pkg:golang/github.com/emmansun/gmsm`Other threats	Affected <0.41.1	Fixed in 0.41.1

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Organizations using the GMSM library should immediately upgrade to version 0.41.1 or later, which includes the fix rejecting the point at infinity during SM9 ciphertext verification. If upgrading is not immediately possible, implement additional application-level checks to validate that elliptic curve points are not the point at infinity before decryption. Conduct thorough code audits of cryptographic operations involving SM9 to ensure proper validation of all elliptic curve points and cryptographic inputs. Employ defense-in-depth by combining cryptographic integrity checks with application-layer message authentication codes or signatures. Educate developers and security teams on the risks of improper elliptic curve point validation and the importance of adhering to cryptographic standards. Finally, consider isolating or limiting exposure of systems using vulnerable GMSM versions until patched to reduce attack surface.

Description

Go ShangMi (Commercial Cryptography) Library (GMSM) is a cryptographic library that covers the Chinese commercial cryptographic public algorithms SM2/SM3/SM4/SM9/ZUC. Prior to 0.41.1, the current SM9 decryption implementation contains an infinity-point ciphertext forgery vulnerability. The root cause is that, during decryption, the elliptic-curve point C1 in the ciphertext is only deserialized and checked to be on the curve, but the implementation does not explicitly reject the point at infinity. In the current implementation, an attacker can construct C1 as the point at infinity, causing the bilinear pairing result to degenerate into the identity element in the GT group. As a result, a critical part of the key derivation input becomes a predictable constant. An attacker who only knows the target user's UID can derive the decryption key material and then forge a ciphertext that passes the integrity check. This vulnerability is fixed in 0.41.1.

Impact

This vulnerability undermines the integrity of cryptographic operations using the SM9 algorithm in the GMSM library. Organizations relying on GMSM for secure communications, digital signatures, or identity-based encryption may face risks of message forgery and unauthorized data manipulation. Attackers can craft malicious ciphertexts that appear valid, potentially enabling impersonation, injection of false data, or bypassing of security controls dependent on SM9. Although confidentiality is not directly impacted, the ability to forge ciphertexts can lead to trust erosion in secure communications and cryptographic protocols. The vulnerability is exploitable remotely without authentication or user interaction, increasing the risk of widespread exploitation if unpatched. Given the use of GMSM in Chinese commercial cryptography contexts, sectors such as government, finance, telecommunications, and critical infrastructure in China and regions using these cryptographic standards are particularly at risk. The lack of known exploits suggests limited immediate threat but the high severity score warrants prompt remediation to prevent future attacks.

CWE-347Improper Verification of Cryptographic Signature (opens in a new tab)
Base weaknessOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
OWASP Cheat Sheets
XML Security (opens in a new tab)
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
REST Assessment (opens in a new tab)
Cross-Site Request Forgery Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.2 (opens in a new tab)
V3.5.3 (opens in a new tab)
V13.2.6 (opens in a new tab)
Attack patterns
Padding Oracle Crypto Attack (opens in a new tab)
Signature Spoofing by Improper Validation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

github.com/emmansun/gmsm/security/advisories/GHSA-5xxp-2vrj-x855 (opens in a new tab)

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 20 Mar 2026, 23:20 UTC

WeaknessesCWE-347

Technical details

References

Community reviews

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