Vulnerability-Lookup

PYSEC-2026-3754

Vulnerability from pysec - Published: 2026-08-17 11:16 - Updated: 2026-09-02 08:34

Details

openssl_encrypt versions before 1.4.0 use Python's non-cryptographic random module for steganographic pixel selection in the generate_pseudorandom_sequence function. Attackers who know the password can recover the Mersenne Twister state from approximately 624 outputs and predict pixel locations containing hidden data for extraction.

Severity

8.7 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Impacted products

Name	purl
openssl-encrypt	pkg:pypi/openssl-encrypt

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {},
      "package": {
        "ecosystem": "PyPI",
        "name": "openssl-encrypt",
        "purl": "pkg:pypi/openssl-encrypt"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.2.2",
        "0.2.3",
        "0.2.4",
        "0.2.5",
        "0.2.6",
        "0.3.0",
        "0.3.1",
        "0.3.2",
        "0.3.3",
        "0.4.0",
        "0.4.1",
        "0.4.2",
        "0.4.3",
        "0.4.4",
        "0.5.0",
        "0.5.1",
        "0.5.3",
        "0.6.0rc1",
        "0.7.0rc2",
        "0.7.1",
        "0.7.2",
        "0.8.0",
        "0.8.1",
        "0.8.2",
        "0.9.2",
        "1.0.0",
        "1.0.1",
        "1.0.2",
        "1.0.3",
        "1.1.0",
        "1.2.0",
        "1.2.1",
        "1.3.0",
        "1.3.1",
        "1.3.2",
        "1.3.3",
        "1.3.4",
        "1.3.5",
        "1.4.0b3",
        "1.4.0b4",
        "1.4.0b5",
        "1.4.0b6",
        "1.4.0b7",
        "1.4.0b8"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-74874",
    "GHSA-vfgx-5q85-58q3"
  ],
  "details": "openssl_encrypt versions before 1.4.0 use Python\u0027s non-cryptographic random module for steganographic pixel selection in the generate_pseudorandom_sequence function. Attackers who know the password can recover the Mersenne Twister state from approximately 624 outputs and predict pixel locations containing hidden data for extraction.",
  "id": "PYSEC-2026-3754",
  "modified": "2026-09-02T08:34:39.407236Z",
  "published": "2026-08-17T11:16:41.813Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vfgx-5q85-58q3"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/openssl-encrypt-before-weak-prng-steganography-pixel-selection"
    }
  ],
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-74874 (GCVE-0-2026-74874)

Vulnerability from cvelistv5 – Published: 2026-08-17 11:04 – Updated: 2026-08-17 16:04

Title

openssl_encrypt before 1.4.0 Weak PRNG Steganography Pixel Selection

Summary

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-17 15:44 UTC

CWE

CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/jahlives/openssl_encrypt/secur…	vendor-advisory
https://www.vulncheck.com/advisories/openssl-encr…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
jahlives	openssl_encrypt	Affected: 0 , < 1.4.0 (semver) Unaffected: 1.4.0 (semver)

Date Public

2026-02-10 00:00

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-74874",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-17T15:44:44.405610Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-17T16:04:06.261Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:pypi/openssl_encrypt",
          "product": "openssl_encrypt",
          "vendor": "jahlives",
          "versions": [
            {
              "lessThan": "1.4.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "1.4.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "datePublic": "2026-02-10T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "openssl_encrypt versions before 1.4.0 use Python\u0027s non-cryptographic random module for steganographic pixel selection in the generate_pseudorandom_sequence function. Attackers who know the password can recover the Mersenne Twister state from approximately 624 outputs and predict pixel locations containing hidden data for extraction."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-338",
              "description": "Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T11:04:42.912Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-vfgx-5q85-58q3)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vfgx-5q85-58q3"
        },
        {
          "name": "VulnCheck Advisory: openssl_encrypt before 1.4.0 Weak PRNG Steganography Pixel Selection",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/openssl-encrypt-before-weak-prng-steganography-pixel-selection"
        }
      ],
      "title": "openssl_encrypt before 1.4.0 Weak PRNG Steganography Pixel Selection",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-74874",
    "datePublished": "2026-08-17T11:04:42.912Z",
    "dateReserved": "2026-08-17T10:31:04.593Z",
    "dateUpdated": "2026-08-17T16:04:06.261Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

GHSA-VFGX-5Q85-58Q3

Vulnerability from github – Published: 2026-03-31 23:43 – Updated: 2026-03-31 23:43

Summary

openssl-encrypt has non-cryptographic PRNG used for steganography pixel selection

Details

Summary

The generate_pseudorandom_sequence() function in openssl_encrypt/plugins/steganography/core/utils.py at lines 89-91 uses Python's random module (Mersenne Twister) for steganographic pixel/sample selection.

Affected Code

random.seed(seed)
sequence = random.sample(range(max_value), min(length, max_value))
return sequence

Additionally, the steganography password is stored as a plain Python string (not SecureBytes) and only 8 bytes (64 bits) of the SHA-256 hash are used for the seed, reducing effective security to 64 bits.

Impact

The Mersenne Twister's state can be recovered from approximately 624 outputs. An attacker who knows or guesses the password can predict the PRNG sequence and determine exactly which pixels contain hidden data, potentially extracting the hidden data without the password.

Recommended Fix

Use HMAC-DRBG or secrets module for cryptographically secure pixel selection
Use full 32-byte SHA-256 output as seed material
Store the password in SecureBytes instead of a plain string

Fix

Fixed in commit 09e96e0 on branch releases/1.4.x — replaced random.seed(hash(password)) with HMAC-SHA256 based CSPRNG (Fisher-Yates shuffle) and numpy Generator with HMAC-derived seeds across all steganography format modules.

Severity

6.6 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "openssl-encrypt"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-330"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-31T23:43:06Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nThe `generate_pseudorandom_sequence()` function in `openssl_encrypt/plugins/steganography/core/utils.py` at **lines 89-91** uses Python\u0027s `random` module (Mersenne Twister) for steganographic pixel/sample selection.\n\n### Affected Code\n\n```python\nrandom.seed(seed)\nsequence = random.sample(range(max_value), min(length, max_value))\nreturn sequence\n```\n\nAdditionally, the steganography password is stored as a plain Python string (not `SecureBytes`) and only 8 bytes (64 bits) of the SHA-256 hash are used for the seed, reducing effective security to 64 bits.\n\n### Impact\n\nThe Mersenne Twister\u0027s state can be recovered from approximately 624 outputs. An attacker who knows or guesses the password can predict the PRNG sequence and determine exactly which pixels contain hidden data, potentially extracting the hidden data without the password.\n\n### Recommended Fix\n\n- Use HMAC-DRBG or `secrets` module for cryptographically secure pixel selection\n- Use full 32-byte SHA-256 output as seed material\n- Store the password in `SecureBytes` instead of a plain string\n\n### Fix\n\nFixed in commit `09e96e0` on branch `releases/1.4.x` \u2014 replaced random.seed(hash(password)) with HMAC-SHA256 based CSPRNG (Fisher-Yates shuffle) and numpy Generator with HMAC-derived seeds across all steganography format modules.",
  "id": "GHSA-vfgx-5q85-58q3",
  "modified": "2026-03-31T23:43:06Z",
  "published": "2026-03-31T23:43:06Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vfgx-5q85-58q3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jahlives/openssl_encrypt/commit/09e96e090417d34d2f533f6810d3cd4f77810101"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jahlives/openssl_encrypt"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "openssl-encrypt has non-cryptographic PRNG used for steganography pixel selection"
}

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.

Action not permitted

PYSEC-2026-3754

CVE-2026-74874 (GCVE-0-2026-74874)

GHSA-VFGX-5Q85-58Q3

Summary

Affected Code

Impact

Recommended Fix

Fix

Tags

Sightings

Nomenclature