mirage-crypto up to 2.1.x Authentication Decryption missing encryption

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.47+

Summaryinfo

A vulnerability categorized as problematic has been discovered in mirage-crypto up to 2.1.x. The affected element is the function AES.GCM.authenticate_decrypt_into/Chacha20.authenticate_decrypt_into of the component Authentication Decryption. Such manipulation leads to missing encryption. This vulnerability is listed as CVE-2026-87732. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in mirage-crypto up to 2.1.x. Affected by this issue is the function AES.GCM.authenticate_decrypt_into/Chacha20.authenticate_decrypt_into of the component Authentication Decryption. The manipulation with an unknown input leads to a missing encryption vulnerability. Using CWE to declare the problem leads to CWE-311. The product does not encrypt sensitive or critical information before storage or transmission. Impacted is confidentiality. CVE summarizes:

An issue was discovered in the mirage-crypto package before 2.2.0 for OCaml. The AES.GCM.authenticate_decrypt_into and Chacha20.authenticate_decrypt_into functions write the decrypted plaintext into a caller-provided buffer and only then compares the tag. On a forged tag, the functions returns false, but the destination buffer already holds the full plaintext.

The advisory is shared for download at osv.dev. This vulnerability is handled as CVE-2026-87732 since 09/09/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1600.

Upgrading to version 2.2.0 eliminates this vulnerability.

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Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.9

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.2
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing encryption
CWE: CWE-311 / CWE-310
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mirage-crypto 2.2.0

Timelineinfo

09/09/2026 Advisory disclosed
09/09/2026 +0 days CVE reserved
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: osv.dev
Status: Confirmed

CVE: CVE-2026-87732 (🔒)
GCVE (CVE): GCVE-0-2026-87732
GCVE (VulDB): GCVE-100-401528

Entryinfo

Created: 09/09/2026 06:46
Changes: 09/09/2026 06:46 (63)
Complete: 🔍
Cache ID: 216::103

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