How severe is CVE-2018-12454?

CVE-2018-12454 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-12454 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-12454?

CVE-2018-12454 affects 1000guess 1000 Guess. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-12454?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-12454 published?

CVE-2018-12454 was published on 2018-06-17 and last updated on 2026-06-17.

CVE-2018-12454

CVE-2018-12454 is a high-severity vulnerability in 1000guess 1000 Guess with a CVSS 3.x base score of 7.5. 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-338.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-338
Affected product: 1000guess 1000 Guess
Published: 2018-06-17
Last modified: 2026-06-17

Description

The _addguess function of a simplelottery smart contract implementation for 1000 Guess, an Ethereum gambling game, generates a random value with publicly readable variables such as the current block information and a private variable (which can be read with a getStorageAt call). Therefore, it allows attackers to always win and get rewards.

Frequently asked questions

What is CVE-2018-12454?: The _addguess function of a simplelottery smart contract implementation for 1000 Guess, an Ethereum gambling game, generates a random value with publicly readable variables such as the current block information and a private variable (which can be read with a getStorageAt call). Therefore, it allows attackers to always win and get rewards.
How severe is CVE-2018-12454?: CVE-2018-12454 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-12454 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-12454?: CVE-2018-12454 affects 1000guess 1000 Guess. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-12454?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-12454 published?: CVE-2018-12454 was published on 2018-06-17 and last updated on 2026-06-17.

References

https://medium.com/%40jonghyk.song/attack-on-pseudo-random-number-generator-prng-used-in-1000-guess-an-ethereum-lottery-game-7b76655f953d

Affected products (1)

cpe:2.3:a:1000guess:1000_guess:-:*:*:*:*:*:*:*

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