CVE-2026-18503
Super-linear CPU usage for unbounded input to csv.Sniffer.sniff()
No known exploitation. EPSS puts it in the 2nd percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
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
0.1% chance of exploitation activity in the next 30 days, which ranks it in the 2nd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 8 days, from the signal feeds we watch.
- Record updated
- OpenVAS check added
- Record updated
- Record updated
- Publishedweakness classified, record updated, record updated
Affected products
Technical detail
Weaknesses
Sources
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