CVE-2017-1000257

Status: ModifiedCritical (9.1)—

An IMAP FETCH response line indicates the size of the returned data, in number of bytes. When that response says the data is zero bytes, libcurl would pass on that (non-existing) data with a pointer and the size (zero) to the deliver-data function. libcurl's deliver-data function treats zero as a magic number and invokes strlen() on the data to figure out the length. The strlen() is called on a heap based buffer that might not be zero terminated so libcurl might read beyond the end of it into whatever memory lies after (or just crash) and then deliver that to the application as if it was actually downloaded.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Base score: 9.1

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 6.22%
Percentile among all scored CVEs: 93
Score date: 10/6/2026

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).

Affected technologies (2)

Debian — Debian Linux Haxx — Libcurl

CWEs

CWE-119
CWE-119

References

Raw JSON (NVD)

Show

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