CVE-2021-36386
No known exploitation. EPSS puts it in the 85th percentile. Fixed in 6.4.20.
What to do
Find your product and version, then upgrade to the build on the right.
- FetchmailAffected: < 6.4.20Upgrade to: 6.4.20Stated by: NVD
- ООО «Ред Софт» РЕД ОСAffected: 7.2 МуромUpgrade to: not statedStated by: BDU
- Eric S Raymond fetchmailAffected: от 6.4.0 до 6.4.20Upgrade to: not statedStated by: BDU
- ООО «РусБИТех-Астра» Astra Linux Special EditionAffected: 1.7Upgrade to: not statedStated by: BDU
- АО «НППКТ» ОСОН ОСнова ОnyxAffected: до 2.5Upgrade to: not statedStated by: BDU
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
report_vbuild in report.c in Fetchmail before 6.4.20 sometimes omits initialization of the vsnprintf va_list argument, which might allow mail servers to cause a denial of service or possibly have unspecified other impact via long error messages. NOTE: it is unclear whether use of Fetchmail on any realistic platform results in an impact beyond an inconvenience to the client user.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
2.6% chance of exploitation activity in the next 30 days, which ranks it in the 85th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1792 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
And 1 more affected product. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 7.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
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