CVE-2025-27105
CVE-2025-27105 is a critical-severity vulnerability in Vyperlang Vyper with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- CVSS v4: 2.3
- EPSS exploit prediction: 1% (41st percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2025-4283
- Weakness: CWE-787
- Affected product: Vyperlang Vyper
- Published:
- Last modified:
Description
vyper is a Pythonic Smart Contract Language for the EVM. Vyper handles AugAssign statements by first caching the target location to avoid double evaluation. However, in the case when target is an access to a DynArray and the rhs modifies the array, the cached target will evaluate first, and the bounds check will not be re-evaluated during the write portion of the statement. This issue has been addressed in version 0.4.1 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
Frequently asked questions
- What is CVE-2025-27105?
- vyper is a Pythonic Smart Contract Language for the EVM. Vyper handles AugAssign statements by first caching the target location to avoid double evaluation. However, in the case when target is an access to a DynArray and the rhs modifies the array, the cached target will evaluate first, and the bounds check will not be re-evaluated during the write portion of the statement. This issue has been addressed in version 0.4.1 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
- How severe is CVE-2025-27105?
- CVE-2025-27105 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
- Is CVE-2025-27105 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2025-27105?
- CVE-2025-27105 affects Vyperlang Vyper. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2025-27105?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2025-27105 have an EU (EUVD) identifier?
- Yes. CVE-2025-27105 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-4283.
- When was CVE-2025-27105 published?
- CVE-2025-27105 was published on 2025-02-21 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*
More vulnerabilities in Vyperlang Vyper
- CVE-2024-24563 — Critical (CVSS 9.8): Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine. Arrays can be keyed by a signed integer,…
- CVE-2024-24561 — Critical (CVSS 9.8): Vyper is a pythonic Smart Contract Language for the ethereum virtual machine. In versions 0.3.10 and earlier, the…
- CVE-2022-24845 — High (CVSS 8.8): Vyper is a pythonic Smart Contract Language for the ethereum virtual machine. In affected versions, the return of…
- CVE-2022-29255 — High (CVSS 8.2): Vyper is a Pythonic Smart Contract Language for the ethereum virtual machine. In versions prior to 0.3.4 when a calling…
- CVE-2023-42443 — High (CVSS 8.1): Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). In version 0.3.9 and prior, under…
- CVE-2025-27104 — High (CVSS 7.5): vyper is a Pythonic Smart Contract Language for the EVM. Multiple evaluation of a single expression is possible in the…
All CVEs affecting Vyperlang Vyper →
Other CWE-787 (Out-of-bounds Write) vulnerabilities
- CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
- CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src modules). This vulnerability is…
- CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
- CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
- CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
- CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…