Medium severity · published Sep 9, 2026
CVE-2026-87733
An issue was discovered in the mirage-crypto-ec function before 2.2.0 for OCaml
6.2
CVSS
0.2%
EPSS
No
On KEV
Description
An issue was discovered in the mirage-crypto-ec function before 2.2.0 for OCaml. The ECDSA functions {P256,P384,P521}.Dsa.pub_of_octets accept 0x00, the encoding of the point at infinity, as a public key. With that public key, signatures can be forged without a private key.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
mirage-crypto-ec · OCaml
before 2.2.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-87733
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-87733
osv.dev
https://osv.dev/vulnerability/OSEC-2026-13
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