Vulnerability-Lookup

GHSA-3HPV-HGVQ-792M

Vulnerability from github – Published: 2023-12-12 18:31 – Updated: 2025-11-04 21:30

Details

The NSS code used for checking PKCS#1 v1.5 was leaking information useful in mounting Bleichenbacher-like attacks. Both the overall correctness of the padding as well as the length of the encrypted message was leaking through timing side-channel. By sending large number of attacker-selected ciphertexts, the attacker would be able to decrypt a previously intercepted PKCS#1 v1.5 ciphertext (for example, to decrypt a TLS session that used RSA key exchange), or forge a signature using the victim's key. The issue was fixed by implementing the implicit rejection algorithm, in which the NSS returns a deterministic random message in case invalid padding is detected, as proposed in the Marvin Attack paper. This vulnerability affects NSS < 3.61.

Severity

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Show details on source website

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  "id": "GHSA-3hpv-hgvq-792m",
  "modified": "2025-11-04T21:30:52Z",
  "published": "2023-12-12T18:31:34Z",
  "references": [
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      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-4421"
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    },
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      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2023/10/msg00039.html"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2023-53"
    }
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  "schema_version": "1.4.0",
  "severity": [
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      "type": "CVSS_V3"
    }
  ]
}

CVE-2023-4421 (GCVE-0-2023-4421)

Vulnerability from cvelistv5 – Published: 2023-12-12 17:02 – Updated: 2025-11-04 19:25

Summary

Severity

No CVSS data available.

CWE

Timing side-channel in PKCS#1 v1.5 decryption depadding code

Assigner

mozilla mitre root

References

3 references

URL	Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1651411
https://www.mozilla.org/security/advisories/mfsa2…
https://lists.debian.org/debian-lts-announce/2023…

Impacted products

1 product

Vendor	Product	Version
Mozilla	NSS	Affected: unspecified , < 3.61 (custom)

Credits

Hubert Kario

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

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.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

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