CVE-2025-37984 (GCVE-0-2025-37984)

Vulnerability from cvelistv5 – Published: 2025-05-20 17:09 – Updated: 2026-08-05 11:58
VLAI
Title
crypto: ecdsa - Harden against integer overflows in DIV_ROUND_UP()
Summary
In the Linux kernel, the following vulnerability has been resolved: crypto: ecdsa - Harden against integer overflows in DIV_ROUND_UP() Herbert notes that DIV_ROUND_UP() may overflow unnecessarily if an ecdsa implementation's ->key_size() callback returns an unusually large value. Herbert instead suggests (for a division by 8): X / 8 + !!(X & 7) Based on this formula, introduce a generic DIV_ROUND_UP_POW2() macro and use it in lieu of DIV_ROUND_UP() for ->key_size() return values. Additionally, use the macro in ecc_digits_from_bytes(), whose "nbytes" parameter is a ->key_size() return value in some instances, or a user-specified ASN.1 length in the case of ecdsa_get_signature_rs().
Severity
7 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 55779f26eab9af12474a447001bd17070f055712 , < f02f0218be412cff1c844addf58e002071be298b (git)
Affected: c6ab5c915da460c0397960af3c308386c3f3247b , < f2133b849ff273abddb6da622daddd8f6f6fa448 (git)
Affected: c6ab5c915da460c0397960af3c308386c3f3247b , < 921b8167f10708e38080f84e195cdc68a7a561f1 (git)
Affected: c6ab5c915da460c0397960af3c308386c3f3247b , < b16510a530d1e6ab9683f04f8fb34f2e0f538275 (git)
Affected: 6.6.70 , < 6.6.99 (semver)
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Linux Linux Affected: 6.10
Unaffected: 0 , < 6.10 (semver)
Unaffected: 6.6.99 , ≤ 6.6.* (semver)
Unaffected: 6.12.39 , ≤ 6.12.* (semver)
Unaffected: 6.14.5 , ≤ 6.14.* (semver)
Unaffected: 6.15 , ≤ * (original_commit_for_fix)
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            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: crypto: ecdsa - Protecci\u00f3n contra desbordamientos de enteros en DIV_ROUND_UP(). Herbert se\u00f1ala que DIV_ROUND_UP() puede desbordarse innecesariamente si la funci\u00f3n de retorno -\u0026gt;key_size() de una implementaci\u00f3n de ecdsa devuelve un valor inusualmente grande. En su lugar, Herbert sugiere (para una divisi\u00f3n entre 8): X / 8 + !!(X y 7). Con base en esta f\u00f3rmula, introduzca una macro gen\u00e9rica DIV_ROUND_UP_POW2() y \u00fasela en lugar de DIV_ROUND_UP() para los valores de retorno de -\u0026gt;key_size(). Adem\u00e1s, utilice la macro en ecc_digits_from_bytes(), cuyo par\u00e1metro \"nbytes\" es un valor de retorno de -\u0026gt;key_size() en algunos casos, o una longitud ASN.1 especificada por el usuario en el caso de ecdsa_get_signature_rs()."
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      "product_status:known_affected": "232",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: crypto: ecdsa - Harden against integer overflows in DIV_ROUND_UP()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-37984.json",
      "version": "3"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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