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NVD / CVE Program· CNA mitre

CVE-2012-5671: Heap-based buffer overflow in the dkim_exim_query_dns_txt function in dkim.c in Exim 4.70 through 4.80, when DKIM support is enabled and…

MediumCVSS 6.8 · v2.0—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 30/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 8.3% (FIRST EPSS); higher than 95% of all records.
  • Fixed version: exim4 (Debian:12) 4.80-5.1; exim4 (Debian:6.0) 4.72-6+squeeze3; exim (openSUSE:Tumbleweed) 4.86.2-2.2.

Low priority for now. Upgrade to exim4 (Debian:12) 4.80-5.1; exim4 (Debian:6.0) 4.72-6+squeeze3; exim (openSUSE:Tumbleweed) 4.86.2-2.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Heap-based buffer overflow in the dkim_exim_query_dns_txt function in dkim.c in Exim 4.70 through 4.80, when DKIM support is enabled and acl_smtp_connect and acl_smtp_rcpt are not set to "warn control = dkim_disable_verify," allows remote attackers to execute arbitrary code via an email from a malicious DNS server.

Published
Oct 31, 2012
Updated
Jun 16, 2026
EPSS
8.3% · 95th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
27 / 40 · 6.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
3 / 30 · 8.3%

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2012-5671

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
eximexim

Using exim? Add it to your stack and be the first to know about CVEs like this one. (Email server)

Watch new CVEs for exim

When you'll hear from us

  • when a new CVE affecting this product is published
  • when a record in your stack enters KEV or is weaponized

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits every 10 minutes on paid plans, on the hour on the free plan.

Your free account also gets you

  • CVE alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every Monday

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • exim exim4.70
  • exim exim4.71
  • exim exim4.72
  • exim exim4.73
  • exim exim4.74
  • exim exim4.75
  • exim exim4.76
  • exim exim4.77
  • exim exim4.80

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12exim4before 4.80-5.14.80-5.1
Debian:6.0exim4before 4.72-6+squeeze34.72-6+squeeze3
openSUSE:Tumbleweedeximbefore 4.86.2-2.24.86.2-2.2

Same product

exim: all records

Other highest-scoring records for the same primary product.

  • CVE-2019-10149A flaw was found in Exim versions 4.87 to 4.91 (inclusive).KEV
    99Now
  • CVE-2018-6789An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1.KEV
    94Now
  • CVE-2010-4344Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code…KEV
    91Now

Published before and after this one in the same product

  • ← EarlierCVE-2011-1407May 16, 2011 · The DKIM implementation in Exim 4.7x before 4.76 permits matching for DKIM identities to apply to lookup items, instead of only strings…
    31Monitor
  • ← EarlierCVE-2011-1764Oct 4, 2011 · Format string vulnerability in the dkim_exim_verify_finish function in src/dkim.c in Exim before 4.76 might allow remote attackers to…
    31Monitor
  • Later →CVE-2014-2957Sep 4, 2014 · The dmarc_process function in dmarc.c in Exim before 4.82.1, when EXPERIMENTAL_DMARC is enabled, allows remote attackers to execute…
    29Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:exim44.80-5.1 · Debian:12Package registry (OSV)
opensuse:exim4.86.2-2.2 · openSUSE:TumbleweedPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

    If successful

    Confidentiality
    P · data can be read
    Integrity
    P · data or configuration can be modified
    Availability
    P · the service can be disrupted
    Attack complexity
    M
    Confidentiality impact
    P
    Integrity impact
    P
    Availability impact
    P

    Weakness class (CWE)

    CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

    CVSS vector

    AV:N/AC:M/Au:N/C:P/I:P/A:P

    nvd-primary

    Attack context

    MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

    ATT&CK techniques

    —

    References

    Show all references (14 more)

    Vendor advisories and official records. Exploit/PoC links are deliberately left out.

    All records