CVE-2023-49798 | Duplicated execution of subcalls in OpenZeppelin Contracts

OpenZeppelin Contracts is a library for smart contract development. A merge issue when porting the 5.0.1 patch to the 4.9 branch caused a line duplication. In the version of `Multicall.sol` released in `@openzeppelin/[email protected]` and `@openzeppelin/[email protected]`, all subcalls are executed twice. Concretely, this exposes a user to unintentionally duplicate operations like asset transfers. The duplicated delegatecall was removed in version 4.9.5. The 4.9.4 version is marked as deprecated. Users are advised to upgrade. There are no known workarounds for this issue.

Published: 2023-12-09 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-49798 is rated Moderate Risk (46.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.49%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-49798

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-26 0.38% 0.49% +0.12%
2 2025-11-21 0.21% 0.38% +0.16%
3 2025-11-18 0.21%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-49798

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-49798

GitHub Security Advisory for CVE-2023-49798

GHSA-699g-q6qh-q4v8 · Severity: medium · Ecosystem: npm — OpenZeppelin Contracts and Contracts Upgradeable duplicated execution of subcalls in v4.9.4

Affected software / configurations for CVE-2023-49798

Vendor Product Version Raw CPE
openzeppelin contracts 4.9.4 cpe:2.3:a:openzeppelin:contracts:4.9.4:*:*:*:*:node.js:*:*
openzeppelin contracts_upgradeable 4.9.4 cpe:2.3:a:openzeppelin:contracts_upgradeable:4.9.4:*:*:*:*:node.js:*:*

References for CVE-2023-49798

cvelogic Threat Intelligence