Observable Timing Discrepancy in totp-rs

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

totp-rs is a Rust library that permits the creation of 2FA authentification tokens per time-based one-time password (TOTP). Prior to version 1.1.0, token comparison was not constant time, and could theorically be used to guess value of an TOTP token, and thus reuse it in the same time window. The attacker would have to know the password beforehand nonetheless. Starting with patched version 1.1.0, the library uses constant-time comparison. There are currently no known workarounds.

Source published

20 May 2022 19:30:12 UTC

Source modified

23 Apr 2025 18:24:00 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 4.2 CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N

totp-rs is a Rust library that permits the creation of 2FA authentification tokens per time-based one-time password (TOTP). Prior to version 1.1.0, token comparison was not constant time, and could theorically be used to guess value of an TOTP token, and thus reuse it in the same time window. The attacker would have to know the password beforehand nonetheless. Starting with patched version 1.1.0, the library uses constant-time comparison. There are currently no known workarounds.

Source published

May 20, 2022, 7:30:12 PM (timezone not stated)

Source modified

Apr 23, 2025, 6:24:00 PM (timezone not stated)

Observed here

10 Nov 2026 00:07:18 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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EUVD CVSS 3.1 · 4.2 CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N

totp-rs is a Rust library that permits the creation of 2FA authentification tokens per time-based one-time password (TOTP). Prior to version 1.1.0, token comparison was not constant time, and could theorically be used to guess value of an TOTP token, and thus reuse it in the same time window. The attacker would have to know the password beforehand nonetheless. Starting with patched version 1.1.0, the library uses constant-time comparison. There are currently no known workarounds.

Source published

20 May 2022 20:15:10 UTC

Source modified

17 Jun 2026 04:39:46 UTC

Observed here

24 Oct 2026 20:17:18 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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CVSS 3.1 · [email protected] · Secondary · 4.2 CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N

CVSS 3.1 · [email protected] · Primary · 4.4 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N

CVSS 2.0 · [email protected] · Primary · 3.5 AV:N/AC:M/Au:S/C:P/I:N/A:N

### Impact Token comparison was not constant time, and could theorically be used to guess value of an TOTP token, and thus reuse it in the same time window. The attacker would have to know the password beforehand nonetheless. ### Patches Library now used constant-time comparison. ### Workarounds No. ### For more information If you have any questions or comments about this advisory: * Open an issue in [totp-rs](https://github.com/constantoine/totp-rs) * Email us at [[email protected]](mailto:[email protected])

Source published

24 May 2022 21:33:15 UTC

Source modified

8 Nov 2023 04:09:09 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N

Publisher rating · MODERATE

Affecting versions did not compare tokens in constant time, which could make it possible for an attacker to guess the 2fa token of a user. This has been fixed by using using the crate constant_time_eq for comparison.

Source published

9 May 2022 12:00:00 UTC

Source modified

12 Oct 2026 18:00:03 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

OSV · upstream source license applies

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N