How severe is CVE-2023-26557?

CVE-2023-26557 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-2023-26557 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26557?

CVE-2023-26557 affects Iofinnet Tss-lib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-26557?

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-2023-26557 published?

CVE-2023-26557 was published on 2023-04-21 and last updated on 2026-06-17.

CVE-2023-26557

CVE-2023-26557 is a high-severity vulnerability in Iofinnet Tss-lib 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-203.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Iofinnet Tss-lib
Published: 2023-04-21
Last modified: 2026-06-17

Description

io.finnet tss-lib before 2.0.0 can leak the lambda value of a private key via a timing side-channel attack because it relies on Go big.Int, which is not constant time for Cmp, modular exponentiation, or modular inverse. An example leak is in crypto/paillier/paillier.go. (bnb-chain/tss-lib and thorchain/tss are also affected.)

Frequently asked questions

What is CVE-2023-26557?: io.finnet tss-lib before 2.0.0 can leak the lambda value of a private key via a timing side-channel attack because it relies on Go big.Int, which is not constant time for Cmp, modular exponentiation, or modular inverse. An example leak is in crypto/paillier/paillier.go. (bnb-chain/tss-lib and thorchain/tss are also affected.)
How severe is CVE-2023-26557?: CVE-2023-26557 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-2023-26557 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26557?: CVE-2023-26557 affects Iofinnet Tss-lib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-26557?: 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-2023-26557 published?: CVE-2023-26557 was published on 2023-04-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:iofinnet:tss-lib:*:*:*:*:*:*:*:*

More vulnerabilities in Iofinnet Tss-lib

CVE-2023-26556 — Critical (CVSS 9.1): io.finnet tss-lib before 2.0.0 can leak a secret key via a timing side-channel attack because it relies on the…
CVE-2022-47931 — Critical (CVSS 9.1): IO FinNet tss-lib before 2.0.0 allows a collision of hash values.
CVE-2022-47930 — Medium (CVSS 6.8): An issue was discovered in IO FinNet tss-lib before 2.0.0. The parameter ssid for defining a session id is not used…

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