CVE-2016-1531

Status: ModifiedHigh (7)—💥 Exploit

Exim before 4.86.2, when installed setuid root, allows local users to gain privileges via the perl_startup argument.

CVSS

Version: 3.0
Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 6.27%
Percentile among all scored CVEs: 93
Score date: 10/7/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

💥 Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Metasploit module (reliable, widely available exploit) · Exim "perl_startup" Privilege Escalation
Published on Exploit-DB · Exim - 'perl_startup' Local Privilege Escalation (Metasploit) (4/15/2016)
Published on Exploit-DB · Exim < 4.86.2 - Local Privilege Escalation (3/10/2016)
Published on Exploit-DB · Exim 4.84-3 - Local Privilege Escalation (3/9/2016)
Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (1)

Exim — Exim

CWEs

CWE-264

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2016-1531",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 6.9,
          "accessVector": "LOCAL",
          "vectorString": "AV:L/AC:M/Au:N/C:C/I:C/A:C",
          "authentication": "NONE",
          "integrityImpact": "COMPLETE",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "COMPLETE",
          "confidentialityImpact": "COMPLETE"
        },
        "acInsufInfo": false,
        "impactScore": 10,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 3.4,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false
      }
    ],
    "cvssMetricV30": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.0",
          "baseScore": 7,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1
      }
    ]
  },
  "affected": [
    {
      "source": "cret@cert.org",
      "affectedData": [
        {
          "vendor": "n/a",
          "product": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ]
    }
  ],
  "published": "2016-04-07T23:59:04.847",
  "references": [
    {
      "url": "http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00026.html",
      "source": "cret@cert.org"
    },
    {
      "url": "http://packetstormsecurity.com/files/136124/Exim-4.84-3-Local-Root-Privilege-Escalation.html",
      "tags": [
        "Exploit"
      ],
      "source": "cret@cert.org"
    },
    {
      "url": "http://www.debian.org/security/2016/dsa-3517",
      "source": "cret@cert.org"
    },
    {
      "url": "http://www.exim.org/static/doc/CVE-2016-1531.txt",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ],
      "source": "cret@cert.org"
    },
    {
      "url": "http://www.rapid7.com/db/modules/exploit/unix/local/exim_perl_startup",
      "source": "cret@cert.org"
    },
    {
      "url": "http://www.securitytracker.com/id/1035512",
      "source": "cret@cert.org"
    },
    {
      "url": "http://www.ubuntu.com/usn/USN-2933-1",
      "source": "cret@cert.org"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39535/",
      "tags": [
        "Exploit"
      ],
      "source": "cret@cert.org"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39549/",
      "source": "cret@cert.org"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39702/",
      "source": "cret@cert.org"
    },
    {
      "url": "http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00026.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://packetstormsecurity.com/files/136124/Exim-4.84-3-Local-Root-Privilege-Escalation.html",
      "tags": [
        "Exploit"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.debian.org/security/2016/dsa-3517",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.exim.org/static/doc/CVE-2016-1531.txt",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.rapid7.com/db/modules/exploit/unix/local/exim_perl_startup",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.securitytracker.com/id/1035512",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.ubuntu.com/usn/USN-2933-1",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39535/",
      "tags": [
        "Exploit"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39549/",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.exploit-db.com/exploits/39702/",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-264"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Exim before 4.86.2, when installed setuid root, allows local users to gain privileges via the perl_startup argument."
    },
    {
      "lang": "es",
      "value": "Exim en versiones anteriores a 4.86.2, cuando está instalado setuid root, permite a usuarios locales obtener privilegios a través del argumento perl_startup."
    }
  ],
  "lastModified": "2026-06-17T00:42:07.677",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E87F70CB-408F-4899-905C-238E45B0FDCE",
              "versionEndIncluding": "4.86"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "cret@cert.org"
}