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CVE-2010-4344 · CVE record: PUBLISHED

Exim Heap-Based Buffer Overflow Vulnerability

n/a n/a

Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session that includes two MAIL commands in conjunction with a large message containing crafted headers, leading to improper rejection logging.

Exploitation evidence

Known exploited · CISA KEV listed

Added 2022-03-25. Ransomware campaign use: Unknown.

CISA required action: Apply updates per vendor instructions.

CISA due date: 2022-04-15. This is the catalog’s deadline, not an assessment of your organization’s exposure.

KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗

Reported products and versions

n/a / n/a

Default status: Not specified

affected: n/a

Fixes and workarounds

No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.

Sources and related reporting

CVE Program record ↗ · Download tracked evidence as JSON

Observed change timeline

History begins when Egret first downloads each source. It is not the complete upstream CVE history.

12 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-12",
  "epss": 0.71706,
  "percentile": 0.9943
}

10 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-10",
  "epss": 0.71706,
  "percentile": 0.99427
}

09 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-09",
  "epss": 0.71706,
  "percentile": 0.99426
}

08 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-08",
  "epss": 0.71706,
  "percentile": 0.99426
}

08 Nov 2026, 00:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

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    "dateReserved": "2010-11-30T00:00:00.000Z",
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07 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-07",
  "epss": 0.71706,
  "percentile": 0.99426
}

06 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
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  "epss": 0.71706,
  "percentile": 0.99425
}

05 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-05",
  "epss": 0.71706,
  "percentile": 0.99425
}

04 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-04",
  "epss": 0.71706,
  "percentile": 0.99424
}

03 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-03",
  "epss": 0.71706,
  "percentile": 0.99423
}

03 Nov 2026, 02:22 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
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  "epss": 0.71706,
  "percentile": 0.99422
}

03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed

Stored KEV snapshot at this observation.

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  "cveID": "CVE-2010-4344",
  "cwes": [
    "CWE-119"
  ],
  "dateAdded": "2022-03-25",
  "dueDate": "2022-04-15",
  "forensicTriage": "No",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "https://nvd.nist.gov/vuln/detail/CVE-2010-4344",
  "product": "Exim",
  "requiredAction": "Apply updates per vendor instructions.",
  "shortDescription": "Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session.",
  "vendorProject": "Exim",
  "vulnerabilityName": "Exim Heap-Based Buffer Overflow Vulnerability"
}

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